diff --git a/.gitmodules b/.gitmodules
index e15dfb45d8..d21535b7f8 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,4 +10,7 @@
 	url = https://github.com/IfcOpenShell/svgfill
 [submodule "src/ifcopenshell-python/test/Sample-BIM-Files"]
 	path = src/ifcopenshell-python/test/Sample-BIM-Files
-	url = https://github.com/IfcOpenShell/ids-test-files
\ No newline at end of file
+	url = https://github.com/IfcOpenShell/ids-test-files
+[submodule "src/ifcconvert/cityjson"]
+	path = src/ifcconvert/cityjson
+	url = https://github.com/IfcOpenShell/ifc-to-cityjson
diff --git a/cmake/CMakeLists.txt b/cmake/CMakeLists.txt
index 69b4c7e122..2d4855b2bc 100644
--- a/cmake/CMakeLists.txt
+++ b/cmake/CMakeLists.txt
@@ -919,6 +919,23 @@ endif()
 
 if (BUILD_CONVERT)
 
+if (WITH_CGAL)
+set(CITYJSON_CONVERT_FILES
+	../src/ifcconvert/cityjson/geobim.cpp
+	../src/ifcconvert/cityjson/global_execution_context.cpp
+	../src/ifcconvert/cityjson/opening_collector.cpp
+	../src/ifcconvert/cityjson/processing.cpp
+	../src/ifcconvert/cityjson/radius_comparison.cpp
+	../src/ifcconvert/cityjson/radius_execution_context.cpp
+	../src/ifcconvert/cityjson/settings.cpp
+	../src/ifcconvert/cityjson/writer.cpp
+)
+
+add_library(cityjson_converter ${CITYJSON_CONVERT_FILES})
+target_include_directories(cityjson_converter PRIVATE ../src)
+set(IFCOPENSHELL_LIBRARIES ${IFCOPENSHELL_LIBRARIES} cityjson_converter)
+endif()
+
 # IfcConvert
 file(GLOB IFCCONVERT_CPP_FILES ../src/ifcconvert/*.cpp)
 file(GLOB IFCCONVERT_H_FILES ../src/ifcconvert/*.h)
@@ -1010,6 +1027,7 @@ ENDIF()
 IF(NOT MINIMAL_BUILD AND BUILD_IFCMAX)
 	ADD_SUBDIRECTORY(../src/ifcmax ifcmax)
 ENDIF()
+
 if (NOT MINIMAL_BUILD)
 if (WITH_CGAL)
 ADD_SUBDIRECTORY(../src/svgfill svgfill)
diff --git a/src/ifcconvert/IfcConvert.cpp b/src/ifcconvert/IfcConvert.cpp
index 0ca7e6e185..85bce2b50d 100644
--- a/src/ifcconvert/IfcConvert.cpp
+++ b/src/ifcconvert/IfcConvert.cpp
@@ -41,6 +41,10 @@
 
 #include "../ifcparse/utils.h"
 
+#ifdef IFOPSH_WITH_CGAL
+#include "./cityjson/geobim.h"
+#endif
+
 #ifdef IFOPSH_WITH_OPENCASCADE
 
 #include <Standard_Version.hxx>
@@ -116,6 +120,9 @@ void print_usage(bool suggest_help = true)
         << "  .svg   SVG            Scalable Vector Graphics (2D floor plan)\n"
 #ifdef WITH_HDF5
 		<< "  .h5    HDF            Hierarchical Data Format storing positions, normals and indices\n"
+#endif
+#ifdef IFOPSH_WITH_CGAL
+		<< "  .city.json            City JSON format for geospatial data\n"
 #endif
 		<< "  .ifc   IFC-SPF        Industry Foundation Classes\n"
 		<< "\n"
@@ -730,6 +737,7 @@ int main(int argc, char** argv) {
 		CACHE = IfcUtil::path::from_utf8(".cache"),
 		HDF = IfcUtil::path::from_utf8(".h5"),
 		XML = IfcUtil::path::from_utf8(".xml"),
+		CITY_JSON = IfcUtil::path::from_utf8(".cityjson"),
 		IFC = IfcUtil::path::from_utf8(".ifc");
 
 	// @todo clean up serializer selection
@@ -779,6 +787,36 @@ int main(int argc, char** argv) {
 		write_log(!quiet);
 		return exit_code;
 	}
+#ifdef IFOPSH_WITH_CGAL
+	else if (output_extension == CITY_JSON) {
+		geobim_settings settings;
+		settings.input_filenames = { IfcUtil::path::to_utf8(input_filename) };
+		settings.cityjson_output_filename = IfcUtil::path::to_utf8(output_filename);
+		// @todo
+		settings.radii = { "0.05" };
+		settings.apply_openings = false;
+		settings.apply_openings_posthoc = true;
+		settings.debug = false;
+		settings.exact_segmentation = false;
+		settings.minkowski_triangles = false;
+		settings.no_erosion = false;
+		settings.spherical_padding = false;
+		
+		settings.settings.set(IfcGeom::IteratorSettings::USE_WORLD_COORDS, false);
+		settings.settings.set(IfcGeom::IteratorSettings::WELD_VERTICES, false);
+		settings.settings.set(IfcGeom::IteratorSettings::SEW_SHELLS, true);
+		settings.settings.set(IfcGeom::IteratorSettings::CONVERT_BACK_UNITS, true);
+		settings.settings.set(IfcGeom::IteratorSettings::DISABLE_TRIANGULATION, true);
+		settings.settings.set(IfcGeom::IteratorSettings::DISABLE_OPENING_SUBTRACTIONS, !settings.apply_openings);
+
+		settings.entity_names = include_filter.values;
+		settings.entity_names_included = true;
+		
+		perform(settings);
+		
+		return 0;
+	}
+#endif
 
     /// @todo Clean up this filter code further.
     std::vector<geom_filter> used_filters;
diff --git a/src/ifcconvert/cityjson b/src/ifcconvert/cityjson
new file mode 160000
index 0000000000..36f8678962
--- /dev/null
+++ b/src/ifcconvert/cityjson
@@ -0,0 +1 @@
+Subproject commit 36f86789623fadc9660aa5f65668ae09435728fb