diff --git a/flex-config/compatible.lua b/flex-config/compatible.lua
index c12912608..d83d32add 100644
--- a/flex-config/compatible.lua
+++ b/flex-config/compatible.lua
@@ -14,8 +14,8 @@ local keep_coastlines = false
 -- Set this to the table name prefix (what used to be option -p|--prefix).
 local prefix = 'planet_osm'
 
--- Set this to true if multipolygons should be written as polygons into db
--- (what used to be option -G|--multi-geometry).
+-- Set this to true if multipolygons should be written as multipolygons into
+-- db (what used to be option -G|--multi-geometry).
 local multi_geometry = false
 
 -- Set this to true if you want an hstore column (what used to be option
@@ -724,7 +724,10 @@ function osm2pgsql.process_relation(object)
     end
 
     if make_boundary or make_polygon then
-        output.way = { create = 'area', multi = multi_geometry }
+        output.way = { create = 'area' }
+        if not multi_geometry then
+            output.way.split_at = 'multi'
+        end
         tables.polygon:add_row(output)
     end
 end
diff --git a/src/geom-transform.cpp b/src/geom-transform.cpp
index 59439cf99..5242678b9 100644
--- a/src/geom-transform.cpp
+++ b/src/geom-transform.cpp
@@ -16,6 +16,7 @@ bool geom_transform_point_t::is_compatible_with(
 
 geom::osmium_builder_t::wkbs_t
 geom_transform_point_t::run(geom::osmium_builder_t *builder,
+                            table_column_type /*target_geom_type*/,
                             osmium::Node const &node) const
 {
     assert(builder);
@@ -49,6 +50,7 @@ bool geom_transform_line_t::is_compatible_with(
 
 geom::osmium_builder_t::wkbs_t
 geom_transform_line_t::run(geom::osmium_builder_t *builder,
+                           table_column_type /*target_geom_type*/,
                            osmium::Way *way) const
 {
     assert(builder);
@@ -59,6 +61,7 @@ geom_transform_line_t::run(geom::osmium_builder_t *builder,
 
 geom::osmium_builder_t::wkbs_t
 geom_transform_line_t::run(geom::osmium_builder_t *builder,
+                           table_column_type /*target_geom_type*/,
                            osmium::Relation const & /*relation*/,
                            osmium::memory::Buffer const &buffer) const
 {
@@ -69,48 +72,61 @@ geom_transform_line_t::run(geom::osmium_builder_t *builder,
 
 bool geom_transform_area_t::set_param(char const *name, lua_State *lua_state)
 {
-    if (std::strcmp(name, "multi") != 0) {
+    if (std::strcmp(name, "multi") == 0) {
+        throw std::runtime_error{
+            "The 'multi' field in the geometry transformation has been"
+            " removed. See docs on how to use 'split_at' instead."};
+    }
+
+    if (std::strcmp(name, "split_at") != 0) {
         return false;
     }
 
-    if (lua_type(lua_state, -1) != LUA_TBOOLEAN) {
+    auto const val = lua_tostring(lua_state, -1);
+
+    if (!val) {
         throw std::runtime_error{
-            "The 'multi' field in a geometry transformation "
-            "description must be a boolean."};
+            "The 'split_at' field in a geometry transformation "
+            "description must be a string."};
     }
-    m_multi = lua_toboolean(lua_state, -1);
 
-    return true;
+    if (std::strcmp(val, "multi") == 0) {
+        m_multi = false;
+        return true;
+    }
+
+    throw std::runtime_error{"Unknown value for 'split_at' field in a geometry"
+                             " transformation: '{}'"_format(val)};
 }
 
 bool geom_transform_area_t::is_compatible_with(
     table_column_type geom_type) const noexcept
 {
-    if (m_multi) {
-        return geom_type == table_column_type::multipolygon ||
-               geom_type == table_column_type::geometry;
-    }
-
     return geom_type == table_column_type::polygon ||
+           geom_type == table_column_type::multipolygon ||
            geom_type == table_column_type::geometry;
 }
 
 geom::osmium_builder_t::wkbs_t
 geom_transform_area_t::run(geom::osmium_builder_t *builder,
+                           table_column_type target_geom_type,
                            osmium::Way *way) const
 {
     assert(builder);
     assert(way);
 
+    geom::osmium_builder_t::wkbs_t result;
+
     if (!way->is_closed()) {
-        return {};
+        return result;
     }
 
-    geom::osmium_builder_t::wkbs_t result;
     result.push_back(builder->get_wkb_polygon(*way));
 
     if (result.front().empty()) {
         result.clear();
+    } else if (target_geom_type == table_column_type::multipolygon) {
+        builder->wrap_in_multipolygon(&result);
     }
 
     return result;
@@ -118,12 +134,15 @@ geom_transform_area_t::run(geom::osmium_builder_t *builder,
 
 geom::osmium_builder_t::wkbs_t
 geom_transform_area_t::run(geom::osmium_builder_t *builder,
+                           table_column_type target_geom_type,
                            osmium::Relation const &relation,
                            osmium::memory::Buffer const &buffer) const
 {
     assert(builder);
 
-    return builder->get_wkb_multipolygon(relation, buffer, m_multi);
+    bool const wrap_multi = target_geom_type == table_column_type::multipolygon;
+
+    return builder->get_wkb_multipolygon(relation, buffer, m_multi, wrap_multi);
 }
 
 std::unique_ptr<geom_transform_t> create_geom_transform(char const *type)
diff --git a/src/geom-transform.hpp b/src/geom-transform.hpp
index 1e84f266b..bad82900a 100644
--- a/src/geom-transform.hpp
+++ b/src/geom-transform.hpp
@@ -32,19 +32,22 @@ class geom_transform_t
 
     virtual geom::osmium_builder_t::wkbs_t
     run(geom::osmium_builder_t * /*builder*/,
+        table_column_type /*target_geom_type*/,
         osmium::Node const & /*node*/) const
     {
         return {};
     }
 
     virtual geom::osmium_builder_t::wkbs_t
-    run(geom::osmium_builder_t * /*builder*/, osmium::Way * /*way*/) const
+    run(geom::osmium_builder_t * /*builder*/,
+        table_column_type /*target_geom_type*/, osmium::Way * /*way*/) const
     {
         return {};
     }
 
     virtual geom::osmium_builder_t::wkbs_t
     run(geom::osmium_builder_t * /*builder*/,
+        table_column_type /*target_geom_type*/,
         osmium::Relation const & /*relation*/,
         osmium::memory::Buffer const & /*buffer*/) const
     {
@@ -60,6 +63,7 @@ class geom_transform_point_t : public geom_transform_t
         noexcept override;
 
     geom::osmium_builder_t::wkbs_t run(geom::osmium_builder_t *builder,
+                                       table_column_type target_geom_type,
                                        osmium::Node const &node) const override;
 
 }; // class geom_transform_point_t
@@ -73,10 +77,12 @@ class geom_transform_line_t : public geom_transform_t
         noexcept override;
 
     geom::osmium_builder_t::wkbs_t run(geom::osmium_builder_t *builder,
+                                       table_column_type target_geom_type,
                                        osmium::Way *way) const override;
 
     geom::osmium_builder_t::wkbs_t
-    run(geom::osmium_builder_t *builder, osmium::Relation const &relation,
+    run(geom::osmium_builder_t *builder, table_column_type target_geom_type,
+        osmium::Relation const &relation,
         osmium::memory::Buffer const &buffer) const override;
 
 private:
@@ -93,14 +99,16 @@ class geom_transform_area_t : public geom_transform_t
         noexcept override;
 
     geom::osmium_builder_t::wkbs_t run(geom::osmium_builder_t *builder,
+                                       table_column_type target_geom_type,
                                        osmium::Way *way) const override;
 
     geom::osmium_builder_t::wkbs_t
-    run(geom::osmium_builder_t *builder, osmium::Relation const &relation,
+    run(geom::osmium_builder_t *builder, table_column_type target_geom_type,
+        osmium::Relation const &relation,
         osmium::memory::Buffer const &buffer) const override;
 
 private:
-    bool m_multi = false;
+    bool m_multi = true;
 
 }; // class geom_transform_area_t
 
diff --git a/src/osmium-builder.cpp b/src/osmium-builder.cpp
index b329a999a..da58fd76f 100644
--- a/src/osmium-builder.cpp
+++ b/src/osmium-builder.cpp
@@ -47,6 +47,26 @@ void add_nodes_to_builder(osmium::builder::WayNodeListBuilder &builder,
 
 namespace geom {
 
+void osmium_builder_t::wrap_in_multipolygon(
+    osmium_builder_t::wkbs_t *geometries)
+{
+    assert(!geometries->empty());
+
+    m_writer.multipolygon_start();
+    for (auto const &p : *geometries) {
+        m_writer.add_sub_geometry(p);
+    }
+    (*geometries)[0] = m_writer.multipolygon_finish(geometries->size());
+    geometries->resize(1);
+}
+
+void osmium_builder_t::wrap_in_multipolygon(osmium_builder_t::wkb_t *geometry)
+{
+    m_writer.multipolygon_start();
+    m_writer.add_sub_geometry(*geometry);
+    *geometry = m_writer.multipolygon_finish(1);
+}
+
 osmium_builder_t::wkb_t
 osmium_builder_t::get_wkb_node(osmium::Location const &loc) const
 {
@@ -145,28 +165,41 @@ osmium_builder_t::get_wkb_polygon(osmium::Way const &way)
 
     auto const wkbs = create_polygons(m_buffer.get<osmium::Area>(0));
 
-    return wkbs.empty() ? wkb_t() : wkbs[0];
+    return wkbs.empty() ? wkb_t{} : wkbs[0];
 }
 
 osmium_builder_t::wkbs_t
 osmium_builder_t::get_wkb_multipolygon(osmium::Relation const &rel,
                                        osmium::memory::Buffer const &ways,
-                                       bool build_multigeoms)
+                                       bool build_multigeoms, bool wrap_multi)
 {
-    wkbs_t ret;
     osmium::area::AssemblerConfig area_config;
     area_config.ignore_invalid_locations = true;
     osmium::area::GeomAssembler assembler{area_config};
 
     m_buffer.clear();
+
+    wkbs_t ret;
     if (assembler(rel, ways, m_buffer)) {
+        auto const &area = m_buffer.get<osmium::Area>(0);
+
+        // This returns a vector of one or more polygons
+        ret = create_polygons(area);
+        assert(!ret.empty());
+
         if (build_multigeoms) {
-            ret.push_back(create_multipolygon(m_buffer.get<osmium::Area>(0)));
+            if (ret.size() > 1 || wrap_multi) {
+                wrap_in_multipolygon(&ret);
+            }
         } else {
-            ret = create_polygons(m_buffer.get<osmium::Area>(0));
+            if (wrap_multi) {
+                for (auto &wkb : ret) {
+                    // wrap each polygon into its own multipolygon
+                    wrap_in_multipolygon(&wkb);
+                }
+            }
         }
     }
-
     return ret;
 }
 
@@ -345,31 +378,6 @@ size_t osmium_builder_t::add_mp_points(osmium::NodeRefList const &nodes)
     return num_points;
 }
 
-osmium_builder_t::wkb_t
-osmium_builder_t::create_multipolygon(osmium::Area const &area)
-{
-    wkb_t ret;
-
-    auto const polys = create_polygons(area);
-
-    switch (polys.size()) {
-    case 0:
-        break; //nothing
-    case 1:
-        ret = polys[0];
-        break;
-    default:
-        m_writer.multipolygon_start();
-        for (auto const &p : polys) {
-            m_writer.add_sub_geometry(p);
-        }
-        ret = m_writer.multipolygon_finish(polys.size());
-        break;
-    }
-
-    return ret;
-}
-
 osmium_builder_t::wkbs_t
 osmium_builder_t::create_polygons(osmium::Area const &area)
 {
diff --git a/src/osmium-builder.hpp b/src/osmium-builder.hpp
index a1f667a46..75bfac29f 100644
--- a/src/osmium-builder.hpp
+++ b/src/osmium-builder.hpp
@@ -30,13 +30,24 @@ class osmium_builder_t
 
     wkbs_t get_wkb_multipolygon(osmium::Relation const &rel,
                                 osmium::memory::Buffer const &ways,
-                                bool build_multigeoms);
+                                bool build_multigeoms, bool wrap_multi = false);
 
     wkbs_t get_wkb_multiline(osmium::memory::Buffer const &ways,
                              double split_at);
 
+    /**
+     * Wrap the geometries (must be one or more polygons) in the parameter
+     * into a single multipolygon which is returned in-place in geometries.
+     */
+    void wrap_in_multipolygon(wkbs_t *geometries);
+
+    /**
+     * Wrap the polygon geometry in the parameter into a multipolygon which
+     * is returned in-place in geometry.
+     */
+    void wrap_in_multipolygon(wkb_t *geometry);
+
 private:
-    wkb_t create_multipolygon(osmium::Area const &area);
     wkbs_t create_polygons(osmium::Area const &area);
     size_t add_mp_points(osmium::NodeRefList const &nodes);
 
diff --git a/src/output-flex.cpp b/src/output-flex.cpp
index 146a46750..596c241f7 100644
--- a/src/output-flex.cpp
+++ b/src/output-flex.cpp
@@ -967,25 +967,28 @@ get_default_transform(flex_table_column_t const &column,
 geom::osmium_builder_t::wkbs_t
 output_flex_t::run_transform(geom::osmium_builder_t *builder,
                              geom_transform_t const *transform,
+                             table_column_type target_geom_type,
                              osmium::Node const &node)
 {
-    return transform->run(builder, node);
+    return transform->run(builder, target_geom_type, node);
 }
 
 geom::osmium_builder_t::wkbs_t
 output_flex_t::run_transform(geom::osmium_builder_t *builder,
                              geom_transform_t const *transform,
+                             table_column_type target_geom_type,
                              osmium::Way const & /*way*/)
 {
     if (get_way_nodes() <= 1U) {
         return {};
     }
-    return transform->run(builder, m_context_way);
+    return transform->run(builder, target_geom_type, m_context_way);
 }
 
 geom::osmium_builder_t::wkbs_t
 output_flex_t::run_transform(geom::osmium_builder_t *builder,
                              geom_transform_t const *transform,
+                             table_column_type target_geom_type,
                              osmium::Relation const &relation)
 {
     m_buffer.clear();
@@ -1000,7 +1003,7 @@ output_flex_t::run_transform(geom::osmium_builder_t *builder,
         m_mid->nodes_get_list(&(way.nodes()));
     }
 
-    return transform->run(builder, relation, m_buffer);
+    return transform->run(builder, target_geom_type, relation, m_buffer);
 }
 
 template <typename OBJECT>
@@ -1035,7 +1038,8 @@ void output_flex_t::add_row(table_connection_t *table_connection,
     }
 
     auto *builder = table_connection->get_builder();
-    auto const wkbs = run_transform(builder, transform, object);
+    auto const wkbs =
+        run_transform(builder, transform, table.geom_column().type(), object);
     for (auto const &wkb : wkbs) {
         m_expire.from_wkb(wkb.c_str(), id);
         write_row(table_connection, object.type(), id, wkb,
diff --git a/src/output-flex.hpp b/src/output-flex.hpp
index b38836aac..2929d7f6a 100644
--- a/src/output-flex.hpp
+++ b/src/output-flex.hpp
@@ -181,16 +181,17 @@ class output_flex_t : public output_t
 
     geom::osmium_builder_t::wkbs_t
     run_transform(geom::osmium_builder_t *builder,
-                  geom_transform_t const *transform, osmium::Node const &node);
-
-    geom::osmium_builder_t::wkbs_t
-    run_transform(geom::osmium_builder_t *builder,
-                  geom_transform_t const *transform, osmium::Way const &way);
+                  geom_transform_t const *transform,
+                  table_column_type target_geom_type, osmium::Node const &node);
 
     geom::osmium_builder_t::wkbs_t
     run_transform(geom::osmium_builder_t *builder,
                   geom_transform_t const *transform,
-                  osmium::Relation const &relation);
+                  table_column_type target_geom_type, osmium::Way const &way);
+
+    geom::osmium_builder_t::wkbs_t run_transform(
+        geom::osmium_builder_t *builder, geom_transform_t const *transform,
+        table_column_type target_geom_type, osmium::Relation const &relation);
 
     template <typename OBJECT>
     void add_row(table_connection_t *table_connection, OBJECT const &object);
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 422e1dcad..6c40f8ef9 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -80,6 +80,7 @@ if (HAVE_LUA)
     set_test(test-output-flex-invalid-geom)
     set_test(test-output-flex-line)
     set_test(test-output-flex-lua-fail)
+    set_test(test-output-flex-multigeom)
     set_test(test-output-flex-nodes)
     set_test(test-output-flex-nogeom)
     set_test(test-output-flex-uni)
diff --git a/tests/data/test_output_flex.lua b/tests/data/test_output_flex.lua
index a3c792ff5..e28e87df5 100644
--- a/tests/data/test_output_flex.lua
+++ b/tests/data/test_output_flex.lua
@@ -117,7 +117,7 @@ function osm2pgsql.process_relation(object)
         tables.polygon:add_row({
             tags = object.tags,
             name = object.tags.name,
-            geom = { create = 'area', multi = false }
+            geom = { create = 'area', split_at = 'multi' }
         })
         return
     end
diff --git a/tests/data/test_output_flex_area.lua b/tests/data/test_output_flex_area.lua
index 8a188a7d1..662868c43 100644
--- a/tests/data/test_output_flex_area.lua
+++ b/tests/data/test_output_flex_area.lua
@@ -27,7 +27,7 @@ end
 function osm2pgsql.process_relation(object)
     polygons:add_row({
         name = object.tags.name,
-        geom = { create = 'area', multi = false }
+        geom = { create = 'area', split_at = 'multi' }
     })
 end
 
diff --git a/tests/data/test_output_flex_invalid_geom.lua b/tests/data/test_output_flex_invalid_geom.lua
index e2ff152d6..feaf25acb 100644
--- a/tests/data/test_output_flex_invalid_geom.lua
+++ b/tests/data/test_output_flex_invalid_geom.lua
@@ -39,7 +39,7 @@ end
 function osm2pgsql.process_relation(object)
     tables.polygon:add_row({
         tags = object.tags,
-        geom = { create = 'area', multi = false }
+        geom = { create = 'area', split_at = 'multi' }
     })
 end
 
diff --git a/tests/data/test_output_flex_multigeom.lua b/tests/data/test_output_flex_multigeom.lua
new file mode 100644
index 000000000..96094e56c
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom.lua
@@ -0,0 +1,32 @@
+
+local polygons = osm2pgsql.define_table{
+    name = 'osm2pgsql_test_polygon',
+    ids = { type = 'area', id_column = 'osm_id' },
+    columns = {
+        { column = 'name', type = 'text' },
+        { column = 'geom', type = test.type }
+    }
+}
+
+function is_empty(some_table)
+    return next(some_table) == nil
+end
+
+function osm2pgsql.process_way(object)
+    if is_empty(object.tags) then
+        return
+    end
+
+    polygons:add_row({
+        name = object.tags.name,
+        geom = { create = 'area' }
+    })
+end
+
+function osm2pgsql.process_relation(object)
+    polygons:add_row({
+        name = object.tags.name,
+        geom = { create = 'area', split_at = test.split_at }
+    })
+end
+
diff --git a/tests/data/test_output_flex_multigeom.osm b/tests/data/test_output_flex_multigeom.osm
new file mode 100644
index 000000000..51d37ebbf
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom.osm
@@ -0,0 +1,51 @@
+<?xml version='1.0' encoding='UTF-8'?>
+<osm version="0.6">
+  <node id="10" lat="0" lon="0"/>
+  <node id="11" lat="0" lon="1"/>
+  <node id="12" lat="1" lon="1"/>
+  <node id="13" lat="1" lon="0"/>
+
+  <node id="14" lat="2" lon="2"/>
+  <node id="15" lat="2" lon="3"/>
+  <node id="16" lat="3" lon="3"/>
+  <node id="17" lat="3" lon="2"/>
+
+  <way id="20">
+    <nd ref="10"/>
+    <nd ref="11"/>
+    <nd ref="12"/>
+    <nd ref="13"/>
+    <nd ref="10"/>
+    <tag k="natural" v="water"/>
+    <tag k="name" v="poly"/>
+  </way>
+
+  <way id="21">
+    <nd ref="10"/>
+    <nd ref="11"/>
+    <nd ref="12"/>
+    <nd ref="13"/>
+    <nd ref="10"/>
+  </way>
+  <way id="22">
+    <nd ref="14"/>
+    <nd ref="15"/>
+    <nd ref="16"/>
+    <nd ref="17"/>
+    <nd ref="14"/>
+  </way>
+
+  <relation id="30">
+    <member type="way" ref="21" role="outer"/>
+    <tag k="type" v="multipolygon"/>
+    <tag k="natural" v="water"/>
+    <tag k="name" v="poly"/>
+  </relation>
+  <relation id="31">
+    <member type="way" ref="21" role="outer"/>
+    <member type="way" ref="22" role="outer"/>
+    <tag k="type" v="multipolygon"/>
+    <tag k="natural" v="water"/>
+    <tag k="name" v="multi"/>
+  </relation>
+</osm>
diff --git a/tests/data/test_output_flex_multigeom_geometry.lua b/tests/data/test_output_flex_multigeom_geometry.lua
new file mode 100644
index 000000000..d3b82e460
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom_geometry.lua
@@ -0,0 +1,5 @@
+
+test = { type = 'geometry' }
+
+dofile(os.getenv('SRCPATH') .. '/data/test_output_flex_multigeom.lua')
+
diff --git a/tests/data/test_output_flex_multigeom_geometry_split.lua b/tests/data/test_output_flex_multigeom_geometry_split.lua
new file mode 100644
index 000000000..79ca67904
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom_geometry_split.lua
@@ -0,0 +1,5 @@
+
+test = { type = 'geometry', split_at = 'multi' }
+
+dofile(os.getenv('SRCPATH') .. '/data/test_output_flex_multigeom.lua')
+
diff --git a/tests/data/test_output_flex_multigeom_multipolygon.lua b/tests/data/test_output_flex_multigeom_multipolygon.lua
new file mode 100644
index 000000000..baaaa02e7
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom_multipolygon.lua
@@ -0,0 +1,5 @@
+
+test = { type = 'multipolygon' }
+
+dofile(os.getenv('SRCPATH') .. '/data/test_output_flex_multigeom.lua')
+
diff --git a/tests/data/test_output_flex_multigeom_multipolygon_split.lua b/tests/data/test_output_flex_multigeom_multipolygon_split.lua
new file mode 100644
index 000000000..fa39ba3db
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom_multipolygon_split.lua
@@ -0,0 +1,5 @@
+
+test = { type = 'multipolygon', split_at = 'multi' }
+
+dofile(os.getenv('SRCPATH') .. '/data/test_output_flex_multigeom.lua')
+
diff --git a/tests/data/test_output_flex_multigeom_polygon.lua b/tests/data/test_output_flex_multigeom_polygon.lua
new file mode 100644
index 000000000..f1d7a863a
--- /dev/null
+++ b/tests/data/test_output_flex_multigeom_polygon.lua
@@ -0,0 +1,5 @@
+
+test = { type = 'polygon', split_at = 'multi' }
+
+dofile(os.getenv('SRCPATH') .. '/data/test_output_flex_multigeom.lua')
+
diff --git a/tests/data/test_output_flex_uni.lua b/tests/data/test_output_flex_uni.lua
index 655e9b83d..1115ae65f 100644
--- a/tests/data/test_output_flex_uni.lua
+++ b/tests/data/test_output_flex_uni.lua
@@ -73,11 +73,11 @@ function osm2pgsql.process_relation(object)
         table1idcol:add_row({
             orig_id = object.id,
             tags = object.tags,
-            geom = { create = 'area', multi = false }
+            geom = { create = 'area', split_at = 'multi' }
         })
         table2idcol:add_row({
             tags = object.tags,
-            geom = { create = 'area', multi = false }
+            geom = { create = 'area', split_at = 'multi' }
         })
         return
     end
diff --git a/tests/data/test_output_flex_validgeom.lua b/tests/data/test_output_flex_validgeom.lua
index 40e7b1701..2815f858a 100644
--- a/tests/data/test_output_flex_validgeom.lua
+++ b/tests/data/test_output_flex_validgeom.lua
@@ -23,7 +23,7 @@ end
 
 function osm2pgsql.process_relation(object)
     polygons:add_row({
-        geom = { create = 'area', multi = false }
+        geom = { create = 'area', split_at='multi' }
     })
 end
 
diff --git a/tests/test-output-flex-multigeom.cpp b/tests/test-output-flex-multigeom.cpp
new file mode 100644
index 000000000..cef645e8a
--- /dev/null
+++ b/tests/test-output-flex-multigeom.cpp
@@ -0,0 +1,104 @@
+#include <catch.hpp>
+
+#include "common-import.hpp"
+#include "common-options.hpp"
+
+static testing::db::import_t db;
+
+static char const *const conf_file_geometry =
+    "test_output_flex_multigeom_geometry.lua";
+static char const *const conf_file_geometry_split =
+    "test_output_flex_multigeom_geometry_split.lua";
+static char const *const conf_file_polygon =
+    "test_output_flex_multigeom_polygon.lua";
+static char const *const conf_file_multipolygon =
+    "test_output_flex_multigeom_multipolygon.lua";
+static char const *const conf_file_multipolygon_split =
+    "test_output_flex_multigeom_multipolygon_split.lua";
+static char const *const data_file = "test_output_flex_multigeom.osm";
+
+TEST_CASE("Use 'geometry' column for area (not splitting multipolygons)")
+{
+    options_t const options = testing::opt_t().flex(conf_file_geometry);
+    REQUIRE_NOTHROW(db.run_file(options, data_file));
+
+    auto conn = db.db().connect();
+
+    CHECK(3 == conn.get_count("osm2pgsql_test_polygon"));
+    CHECK(2 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_Polygon'"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_MultiPolygon'"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = 20"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -30"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -31"));
+}
+
+TEST_CASE("Use 'geometry' column for area (splitting multipolygons)")
+{
+    options_t const options = testing::opt_t().flex(conf_file_geometry_split);
+    REQUIRE_NOTHROW(db.run_file(options, data_file));
+
+    auto conn = db.db().connect();
+
+    CHECK(4 == conn.get_count("osm2pgsql_test_polygon"));
+    CHECK(4 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_Polygon'"));
+    CHECK(0 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_MultiPolygon'"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = 20"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -30"));
+    CHECK(2 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -31"));
+}
+
+TEST_CASE("Use 'polygon' column for area (splitting multipolygons)")
+{
+    options_t const options = testing::opt_t().flex(conf_file_polygon);
+    REQUIRE_NOTHROW(db.run_file(options, data_file));
+
+    auto conn = db.db().connect();
+
+    CHECK(4 == conn.get_count("osm2pgsql_test_polygon"));
+    CHECK(4 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_Polygon'"));
+    CHECK(0 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_MultiPolygon'"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = 20"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -30"));
+    CHECK(2 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -31"));
+}
+
+TEST_CASE("Use 'multipolygon' column for area (not splitting multipolygons)")
+{
+    options_t const options = testing::opt_t().flex(conf_file_multipolygon);
+    REQUIRE_NOTHROW(db.run_file(options, data_file));
+
+    auto conn = db.db().connect();
+
+    CHECK(3 == conn.get_count("osm2pgsql_test_polygon"));
+    CHECK(0 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_Polygon'"));
+    CHECK(3 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_MultiPolygon'"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = 20"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -30"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -31"));
+}
+
+TEST_CASE("Use 'multipolygon' column for area (splitting multipolygons)")
+{
+    options_t const options =
+        testing::opt_t().flex(conf_file_multipolygon_split);
+    REQUIRE_NOTHROW(db.run_file(options, data_file));
+
+    auto conn = db.db().connect();
+
+    CHECK(4 == conn.get_count("osm2pgsql_test_polygon"));
+    CHECK(0 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_Polygon'"));
+    CHECK(4 == conn.get_count("osm2pgsql_test_polygon",
+                              "ST_GeometryType(geom) = 'ST_MultiPolygon'"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = 20"));
+    CHECK(1 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -30"));
+    CHECK(2 == conn.get_count("osm2pgsql_test_polygon", "osm_id = -31"));
+}