diff --git a/code/__defines/map.dm b/code/__defines/map.dm
index 45955c4df8..141f397e56 100644
--- a/code/__defines/map.dm
+++ b/code/__defines/map.dm
@@ -7,9 +7,15 @@
 #define MAP_LEVEL_EMPTY			0x020 // Empty Z-levels that may be used for various things (currently used by bluespace jump)
 #define MAP_LEVEL_CONSOLES		0x040 // Z-levels available to various consoles, such as the crew monitor (when that gets coded in). Defaults to station_levels if unset.
 #define MAP_LEVEL_XENOARCH_EXEMPT 0x080	// Z-levels exempt from xenoarch digsite generation.
+<<<<<<< HEAD
 #define MAP_LEVEL_VORESPAWN		0x100	//CHOMPedit Z-levels players are allowed to late join to via vorish means. Usually non-dangerous locations.
 #define MAP_LEVEL_PERSIST       0x200   // Z-levels where SSpersistence should persist between rounds //CHOMPedit bumped to 0x200 because vorespawn, hopefully this doesn't break things
 #define MAP_LEVEL_MAPPABLE       0x400   // Z-levels where mapping units will work fully //CHOMPedit bumped to 0x400, somethingsomething don't break
+=======
+#define MAP_LEVEL_PERSIST       0x100   // Z-levels where SSpersistence should persist between rounds
+#define MAP_LEVEL_MAPPABLE       0x200   // Z-levels where mapping units will work fully
+#define MAP_LEVEL_BELOW_BLOCKED   0x400   // Z-levels in multiz with level below not meant to be 'normally' accessible
+>>>>>>> d8b0ebf7b4e... Merge pull request #12208 from Heroman3003/tether-passage-block
 
 // Misc map defines.
 #define SUBMAP_MAP_EDGE_PAD 8 // Automatically created submaps are forbidden from being this close to the main map's edge.	//VOREStation Edit
diff --git a/code/game/turfs/turf_changing.dm b/code/game/turfs/turf_changing.dm
index 492f3ef65b..5c51101c52 100644
--- a/code/game/turfs/turf_changing.dm
+++ b/code/game/turfs/turf_changing.dm
@@ -28,7 +28,7 @@
 
 	if(N == /turf/space)
 		var/turf/below = GetBelow(src)
-		if(istype(below) && (air_master.has_valid_zone(below) || air_master.has_valid_zone(src)) && (!istype(below, /turf/unsimulated/wall) && !istype(below, /turf/simulated/sky)))	// VOREStation Edit: Weird open space
+		if(istype(below) && (air_master.has_valid_zone(below) || air_master.has_valid_zone(src)) && !(src.z in using_map.below_blocked_levels) && (!istype(below, /turf/unsimulated/wall) && !istype(below, /turf/simulated/sky)))	// VOREStation Edit: Weird open space
 			N = /turf/simulated/open
 
 	var/obj/fire/old_fire = fire
diff --git a/code/modules/multiz/ladder_assembly_vr.dm b/code/modules/multiz/ladder_assembly_vr.dm
index 44fdcc0c82..24578b7f5c 100644
--- a/code/modules/multiz/ladder_assembly_vr.dm
+++ b/code/modules/multiz/ladder_assembly_vr.dm
@@ -86,6 +86,8 @@
 		if(!T) continue
 		var/obj/structure/ladder_assembly/LA = locate(/obj/structure/ladder_assembly, T)
 		if(!LA) continue
+		if(direction == DOWN && (src.z in using_map.below_blocked_levels)) continue
+		if(direction == UP && (LA.z in using_map.below_blocked_levels)) continue
 		if(LA.state != CONSTRUCTION_WELDED)
 			to_chat(user, "<span class='warning'>\The [LA] [direction == UP ? "above" : "below"] must be secured and welded.</span>")
 			return
diff --git a/maps/tether/tether_defines.dm b/maps/tether/tether_defines.dm
index 4ec8573307..cc5f227370 100644
--- a/maps/tether/tether_defines.dm
+++ b/maps/tether/tether_defines.dm
@@ -354,6 +354,7 @@
 	name = "Asteroid 1"
 	base_turf = /turf/space
 	transit_chance = 33
+	flags = MAP_LEVEL_STATION|MAP_LEVEL_CONTACT|MAP_LEVEL_PLAYER|MAP_LEVEL_CONSOLES|MAP_LEVEL_XENOARCH_EXEMPT|MAP_LEVEL_PERSIST|MAP_LEVEL_BELOW_BLOCKED
 	holomap_offset_x = TETHER_HOLOMAP_MARGIN_X + TETHER_HOLOMAP_CENTER_GUTTER + TETHER_MAP_SIZE
 	holomap_offset_y = TETHER_HOLOMAP_MARGIN_Y + TETHER_MAP_SIZE
 
diff --git a/maps/~map_system/maps.dm b/maps/~map_system/maps.dm
index 5cbabb2aa3..c4df2d45ac 100644
--- a/maps/~map_system/maps.dm
+++ b/maps/~map_system/maps.dm
@@ -39,6 +39,7 @@ var/list/all_maps = list()
 	var/static/list/empty_levels = list()   // Empty Z-levels that may be used for various things
 	var/static/list/vorespawn_levels = list() //Z-levels where players are allowed to vore latejoin to. //CHOMPedit: the number of missing chompedits is giving me an aneurysm
 	var/static/list/mappable_levels = list()// List of levels where mapping or other similar devices might work fully
+	var/static/list/below_blocked_levels = list()// List of levels where mapping or other similar devices might work fully
 	// End Static Lists
 
 	// Z-levels available to various consoles, such as the crew monitor. Defaults to station_levels if unset.
@@ -315,6 +316,9 @@ var/list/all_maps = list()
 	if(flags & MAP_LEVEL_CONSOLES)
 		if (!map.map_levels) map.map_levels = list()
 		map.map_levels += z
+	if(flags & MAP_LEVEL_BELOW_BLOCKED)
+		if (!map.below_blocked_levels) map.below_blocked_levels = list()
+		map.below_blocked_levels += z
 	if(base_turf)
 		map.base_turf_by_z["[z]"] = base_turf
 	if(transit_chance)