diff --git a/src/space.h b/src/space.h
index c294bfae3612c699345bd4a267c40b67cffc2bf1..1b31f0495890a68074225cc68c6acabd1abb53e8 100644
--- a/src/space.h
+++ b/src/space.h
@@ -112,9 +112,6 @@ struct space {
   /*! The minimum top-level cell width allowed. */
   double cell_min;
 
-  /*! Current maximum displacement for particles. */
-  float dx_max;
-
   /*! Space dimensions in number of top-cells. */
   int cdim[3];