diff --git a/geo/Cargo.toml b/geo/Cargo.toml
index c04ff1ad1..1fb2b7af4 100644
--- a/geo/Cargo.toml
+++ b/geo/Cargo.toml
@@ -9,6 +9,7 @@ readme = "../README.md"
 keywords = ["gis", "geo", "geography", "geospatial"]
 autobenches = true
 edition = "2021"
+rust-version = "1.58"
 
 [features]
 use-proj = ["proj"]