diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000..4bcb1e5
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "pxy_city_digital_twins"]
+	path = pxy_city_digital_twins
+	url = ssh://git@git.hadox.org:2222/hadoxmin/pxy_city_digital_twins.git