diff --git a/CHANGELOG.md b/CHANGELOG.md
index 54a2bd6..c297e06 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 - Enhanced `ExtEmDataConnection` with `simulateInternal` method [#398](https://github.com/ie3-institute/simonaAPI/issues/398)
+- Added API structure to the docs [#405](https://github.com/ie3-institute/simonaAPI/issues/405)
 
 ### Changed
 - Splitting up `ExtSimAdapterData` into `SetupData` and a data connection [#400](https://github.com/ie3-institute/simonaAPI/issues/400)
diff --git a/docs/readthedocs/index.md b/docs/readthedocs/index.md
index c18e6ad..47be772 100644
--- a/docs/readthedocs/index.md
+++ b/docs/readthedocs/index.md
@@ -10,6 +10,7 @@ One example are external simulations, that can be used in co-simulations with SI
 :maxdepth: 2
 
 gettingstarted
+structure
 createextsims
 extlinkinterface
 
diff --git a/docs/readthedocs/structure.md b/docs/readthedocs/structure.md
new file mode 100644
index 0000000..29e1ff9
--- /dev/null
+++ b/docs/readthedocs/structure.md
@@ -0,0 +1,45 @@
+# API Structure
+
+This page is mend to provide an overview of the structure of this API.
+
+The API is split into the following parts:
+1. [Data](#data)
+2. [Exceptions](#exceptions)
+3. [Mapping](#mapping)
+4. [Ontology](#ontology)
+5. [Simulation](#simulation)
+6. [Uncategorized](#uncategorized)
+
+## Data
+
+The data package and its sub-packages contains all data-related classes. These are among other things [data connections](/connections/connections),
+data containers and models.
+
+
+## Exceptions
+
+This package contains some exceptions. These can be thrown by the classes of this API.
+
+
+## Mapping
+
+This package contains the `ExtEntityMapping` as well as some `DataTypes` and the `ExtEntityEntry` that are both used in
+the mapping.
+
+## Ontology
+
+All messages that can be exchanged between SIMONA and an external simulation resp. data connection are placed in this
+package.
+
+
+## Simulation
+
+The simulation package contains the available simulations. Currently, only base classes that needs to be implemented are
+provided. The most important class is the [ExtSimulation](/simulations/externalsimulation) as it is the base class for
+all external simulations.
+
+
+## Uncategorized
+
+There is currently only one interface that is not part of a category. This is the [ExtLinkInterface](/extlinkinterface)
+that is used for loading external simulations.