diff --git a/main_gui.c b/main_gui.c
index 89f2611bf0..2c8c1a2aeb 100644
--- a/main_gui.c
+++ b/main_gui.c
@@ -1067,7 +1067,7 @@ static void ResetLandscape(void)
 	_random_seeds[0][0] = InteractiveRandom();
 	_random_seeds[0][1] = InteractiveRandom();
 
-	GenerateWorld(1, 1 << _patches.map_x, 1 << _patches.map_y);
+	GenerateWorld(GW_EMPTY, 1 << _patches.map_x, 1 << _patches.map_y);
 	MarkWholeScreenDirty();
 }
 
diff --git a/misc.c b/misc.c
index 1e2993a21b..8abbc5bf8f 100644
--- a/misc.c
+++ b/misc.c
@@ -122,7 +122,7 @@ void GenerateTrees(void);
 
 void ConvertGroundTilesIntoWaterTiles(void);
 
-void InitializeGame(uint size_x, uint size_y)
+void InitializeGame(int mode, uint size_x, uint size_y)
 {
 	AllocateMap(size_x, size_y);
 
@@ -136,7 +136,7 @@ void InitializeGame(uint size_x, uint size_y)
 	_date_fract = 0;
 	_cur_tileloop_tile = 0;
 
-	{
+	if ((mode & IG_DATE_RESET) == IG_DATE_RESET) {
 		uint starting = ConvertIntDate(_patches.starting_date);
 		if ( starting == (uint)-1) starting = 10958;
 		SetDate(starting);
@@ -189,14 +189,14 @@ void GenerateWorld(int mode, uint size_x, uint size_y)
 	_current_player = OWNER_NONE;
 
 	_generating_world = true;
-	InitializeGame(size_x, size_y);
+	InitializeGame(mode == GW_RANDOM ? 0 : IG_DATE_RESET, size_x, size_y);
 	SetObjectToPlace(SPR_CURSOR_ZZZ, 0, 0, 0);
 
 	// Must start economy early because of the costs.
 	StartupEconomy();
 
 	// Don't generate landscape items when in the scenario editor.
-	if (mode == 1) {
+	if (mode == GW_EMPTY) {
 		// empty world in scenario editor
 		ConvertGroundTilesIntoWaterTiles();
 	} else {
@@ -204,7 +204,7 @@ void GenerateWorld(int mode, uint size_x, uint size_y)
 		GenerateClearTile();
 
 		// only generate towns, tree and industries in newgame mode.
-		if (mode == 0) {
+		if (mode == GW_NEWGAME) {
 			GenerateTowns();
 			GenerateTrees();
 			GenerateIndustries();
@@ -219,7 +219,7 @@ void GenerateWorld(int mode, uint size_x, uint size_y)
 	_generating_world = false;
 
 	// No need to run the tile loop in the scenario editor.
-	if (mode != 1) {
+	if (mode != GW_EMPTY) {
 		for(i=0x500; i!=0; i--)
 			RunTileLoop();
 	}
diff --git a/openttd.c b/openttd.c
index b18850069c..f6daae393b 100644
--- a/openttd.c
+++ b/openttd.c
@@ -279,7 +279,7 @@ static void LoadIntroGame(void)
 		sprintf(filename, "%sopntitle.dat",  _path.second_data_dir);
 		if (SaveOrLoad(filename, SL_LOAD) != SL_OK)
 #endif
-			GenerateWorld(1, 64, 64); // if failed loading, make empty world.
+			GenerateWorld(GW_EMPTY, 64, 64); // if failed loading, make empty world.
 	}
 
 	_pause = 0;
@@ -461,7 +461,7 @@ int ttd_main(int argc, char* argv[])
 	InitializeGUI();
 	IConsoleCmdExec("exec scripts/autoexec.scr 0");
 
-	GenerateWorld(1, 64, 64); // Make the viewport initialization happy
+	GenerateWorld(GW_EMPTY, 64, 64); // Make the viewport initialization happy
 
 #ifdef ENABLE_NETWORK
 	if ((network) && (_network_available)) {
@@ -582,7 +582,7 @@ static void MakeNewGame(void)
 	SetupColorsAndInitialWindow();
 
 	// Randomize world
-	GenerateWorld(0, 1<<_patches.map_x, 1<<_patches.map_y);
+	GenerateWorld(GW_NEWGAME, 1<<_patches.map_x, 1<<_patches.map_y);
 
 	// In a dedicated server, the server does not play
 	if (_network_dedicated) {
@@ -616,7 +616,7 @@ static void MakeNewEditorWorld(void)
 	SetupColorsAndInitialWindow();
 
 	// Startup the game system
-	GenerateWorld(1, 1 << _patches.map_x, 1 << _patches.map_y);
+	GenerateWorld(GW_EMPTY, 1 << _patches.map_x, 1 << _patches.map_y);
 
 	_local_player = OWNER_NONE;
 	MarkWholeScreenDirty();
@@ -797,7 +797,7 @@ void SwitchMode(int new_mode)
 		break;
 
 	case SM_GENRANDLAND: /* Generate random land within scenario editor */
-		GenerateWorld(2, 1<<_patches.map_x, 1<<_patches.map_y);
+		GenerateWorld(GW_RANDOM, 1<<_patches.map_x, 1<<_patches.map_y);
 		// XXX: set date
 		_local_player = OWNER_NONE;
 		MarkWholeScreenDirty();
diff --git a/openttd.h b/openttd.h
index 81ed0b908c..f2ae7684e9 100644
--- a/openttd.h
+++ b/openttd.h
@@ -93,6 +93,21 @@ enum SwitchModes {
 	SM_START_SCENARIO = 10,
 };
 
+
+/* Modes for GenerateWorld */
+enum GenerateWorldModes {
+	GW_NEWGAME  = 0,    /* Generate a map for a new game */
+	GW_EMPTY    = 1,    /* Generate an empty map (sea-level) */
+	GW_RANDOM   = 2,    /* Generate a random map for SE */
+};
+
+/* Modes for InitializeGame, those are _bits_! */
+enum InitializeGameModes {
+	IG_NONE       = 0,  /* Don't do anything special */
+	IG_DATE_RESET = 1,  /* Reset the date when initializing a game */
+};
+
+
 typedef enum TransportTypes {
 	/* These constants are for now linked to the representation of bridges
 	 * and tunnels, so they can be used by GetTileTrackStatus_TunnelBridge
diff --git a/saveload.c b/saveload.c
index 339746342b..827abe6979 100644
--- a/saveload.c
+++ b/saveload.c
@@ -1232,7 +1232,7 @@ static const SaveLoadFormat *GetSavegameFormat(const char *s)
 }
 
 // actual loader/saver function
-void InitializeGame(uint size_x, uint size_y);
+void InitializeGame(int mode, uint size_x, uint size_y);
 extern bool AfterLoadGame(void);
 extern void BeforeSaveGame(void);
 extern bool LoadOldSaveGame(const char *file);
@@ -1363,7 +1363,7 @@ SaveOrLoadResult SaveOrLoad(const char *filename, int mode)
 
 	/* Load a TTDLX or TTDPatch game */
 	if (mode == SL_OLD_LOAD) {
-		InitializeGame(256, 256); // set a mapsize of 256x256 for TTDPatch games or it might get confused
+		InitializeGame(IG_DATE_RESET, 256, 256); // set a mapsize of 256x256 for TTDPatch games or it might get confused
 		if (!LoadOldSaveGame(filename)) return SL_REINIT;
 		_sl_version = 0;
 		AfterLoadGame();
@@ -1487,7 +1487,7 @@ SaveOrLoadResult SaveOrLoad(const char *filename, int mode)
 		/* Old maps were hardcoded to 256x256 and thus did not contain
 		 * any mapsize information. Pre-initialize to 256x256 to not to
 		 * confuse old games */
-		InitializeGame(256, 256);
+		InitializeGame(IG_DATE_RESET, 256, 256);
 
 		SlLoadChunks();
 		fmt->uninit_read();