diff --git a/gtsam/base/FastMap.h b/gtsam/base/FastMap.h
index de79db23b..936c0664e 100644
--- a/gtsam/base/FastMap.h
+++ b/gtsam/base/FastMap.h
@@ -20,7 +20,6 @@
 
 #include <map>
 #include <boost/pool/pool_alloc.hpp>
-#include <boost/serialization/map.hpp>
 #include <boost/serialization/base_object.hpp>
 
 namespace gtsam {