diff --git a/src/ride/track.h b/src/ride/track.h
index c9eabb1c97..52856d520b 100644
--- a/src/ride/track.h
+++ b/src/ride/track.h
@@ -173,7 +173,7 @@ typedef struct {
 	uint8 track_spine_colour[4];					// 0x60
 	uint8 track_rail_colour[4];						// 0x64
 	uint8 track_support_colour[4];					// 0x68
-	uint32 var_6C;									// some flags
+	uint32 var_6C;									// some extra flags. (1 << 31) was used to mark the TD6 as a Six Flags ride.
 	rct_object_entry vehicle_object;				// 0x70
 	uint8 space_required_x;							// 0x80
 	uint8 space_required_y;							// 0x81
diff --git a/src/windows/options.c b/src/windows/options.c
index 779e63d2f7..52718cf0d1 100644
--- a/src/windows/options.c
+++ b/src/windows/options.c
@@ -1199,7 +1199,7 @@ static void window_options_invalidate(rct_window *w)
 
 	case WINDOW_OPTIONS_PAGE_MISC:
 		// unknown park flag can disable real name checkbox
-		if (RCT2_GLOBAL(RCT2_ADDRESS_PARK_FLAGS, uint32) & 0x8000)
+		if (RCT2_GLOBAL(RCT2_ADDRESS_PARK_FLAGS, uint32) & PARK_FLAGS_LOCK_REAL_NAMES_OPTION)
 			w->disabled_widgets |= (1ULL << WIDX_REAL_NAME_CHECKBOX);
 
 		// save plugin data checkbox: visible or not
diff --git a/src/world/park.h b/src/world/park.h
index 2c66a3321a..c9125dbaec 100644
--- a/src/world/park.h
+++ b/src/world/park.h
@@ -41,6 +41,7 @@ enum {
 	PARK_FLAGS_DIFFICULT_GUEST_GENERATION = (1 << 12),
 	PARK_FLAGS_PARK_FREE_ENTRY = (1 << 13),
 	PARK_FLAGS_DIFFICULT_PARK_RATING = (1 << 14),
+	PARK_FLAGS_LOCK_REAL_NAMES_OPTION = (1 << 15),
 	PARK_FLAGS_NO_MONEY_SCENARIO = (1 << 17),  // equivalent to PARK_FLAGS_NO_MONEY, but used in scenario editor
 	PARK_FLAGS_18 = (1 << 18),
 	PARK_FLAGS_SIX_FLAGS_DEPRECATED = (1 << 19)