diff --git a/src/const.h b/src/const.h
index d9e4e09d2081361778df329660db3b6ad8f2e204..6710fe9e52dfdbede468282d84d4441b923a59fe 100644
--- a/src/const.h
+++ b/src/const.h
@@ -37,8 +37,8 @@
 #define const_max_u_change 0.1f
 
 /* Dimensionality of the problem */
-//#define HYDRO_DIMENSION_3D
-#define HYDRO_DIMENSION_2D
+#define HYDRO_DIMENSION_3D
+//#define HYDRO_DIMENSION_2D
 //#define HYDRO_DIMENSION_1D
 
 /* Hydrodynamical adiabatic index. */