diff --git a/raster/r.sim/simlib/output.c b/raster/r.sim/simlib/output.c
index 155f3669465..6b56f60cbe5 100644
--- a/raster/r.sim/simlib/output.c
+++ b/raster/r.sim/simlib/output.c
@@ -71,6 +71,7 @@ void output_walker_as_vector(int tt_minutes, int ndigit,
             Vect_append_point(Points, x, y, z);
             Vect_write_line(&Out, GV_POINT, Points, Cats);
         }
+        Vect_build(&Out);
         /* Close vector file */
         Vect_close(&Out);