diff --git a/openttd.dsp b/openttd.dsp
index 1f333fc53c..0754b01691 100644
--- a/openttd.dsp
+++ b/openttd.dsp
@@ -363,6 +363,10 @@ SOURCE=.\rail.c
 # End Source File
 # Begin Source File
 
+SOURCE=.\road_map.c
+# End Source File
+# Begin Source File
+
 SOURCE=.\saveload.c
 # End Source File
 # Begin Source File
@@ -454,6 +458,10 @@ SOURCE=.\tile.c
 # End Source File
 # Begin Source File
 
+SOURCE=.\tunnel_map.c
+# End Source File
+# Begin Source File
+
 SOURCE=.\unix.c
 # PROP Exclude_From_Build 1
 # End Source File