diff --git a/CMakeLists.txt b/CMakeLists.txt
index d8ff8dd..11f6181 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -26,8 +26,8 @@ if("$ENV{GZ_VERSION}" STREQUAL "harmonic")
   set(GZ_SIM_VER ${gz-sim8_VERSION_MAJOR})
 
   message(STATUS "Compiling against Gazebo Harmonic")
-# Garden
-elseif("$ENV{GZ_VERSION}" STREQUAL "garden")
+# Garden (default)
+elseif("$ENV{GZ_VERSION}" STREQUAL "garden" OR NOT DEFINED "ENV{GZ_VERSION}")
   find_package(gz-cmake3 REQUIRED)
   set(GZ_CMAKE_VER ${gz-cmake3_VERSION_MAJOR})
 
@@ -35,15 +35,8 @@ elseif("$ENV{GZ_VERSION}" STREQUAL "garden")
   set(GZ_SIM_VER ${gz-sim7_VERSION_MAJOR})
 
   message(STATUS "Compiling against Gazebo Garden")
-# Default to Garden
-else()
-  find_package(gz-cmake3 REQUIRED)
-  set(GZ_CMAKE_VER ${gz-cmake3_VERSION_MAJOR})
-
-  gz_find_package(gz-sim7 REQUIRED)
-  set(GZ_SIM_VER ${gz-sim7_VERSION_MAJOR})
-  
-  message(STATUS "Compiling against Gazebo Garden")
+else()  
+  message(FATAL_ERROR "Unsupported GZ_VERSION: $ENV{GZ_VERSION}")
 endif()
 
 # --------------------------------------------------------------------------- #