…walk on the surface. It moves beneath it. The machine is a subterranean borer of staggering proportions — estimated at over 150 meters long and 20 meters in diameter, it t…

…walk on the surface. It moves beneath it. The machine is a subterranean borer of staggering proportions — estimated at over 150 meters long and 20 meters in diameter, it t…

Underground Phoenix — the subterranean city built beneath the ruins of Phoenix, Arizona, after surface temperatures made above-ground habi…

Industrial cargo elevators that descend into the Underworld through vertical shafts bored into the bedrock. The official ones are maintained by Ferrogate and…

Small rail carts running on narrow-gauge track in the deep Underworld mining tunnels. Nobody knows who laid the track or when. The carts are mechanically sim…

The subway lines that descend below the standard metro level into the Underworld. The first three levels are official Ferrogate routes with functioning stati…

A rumored transit system in the deepest levels of the Underworld that uses gravity itself as propulsion — sealed tunnels bored in parabolic arcs through the …

A small, fast hydrofoil designed for Great Lakes racing — an underground sport that draws Tier 2-4 thrill seekers and heavy betting. Skimmers ride on submerg…

A sealed capsule propelled through vacuum tubes beneath the city at extreme speeds. The pneumatic transit system is a relic of an earlier era of GLMZ — the t…

A flat-bottomed electric boat designed to navigate GLMZ's massive storm drain and sewage infrastructure. The tunnel network below the city is large enough to…

A low-profile, motorized sled ridden in a supine position, inches from the ground surface. Originally a gravity-only downhill racing vehicle, GLMZ's version …

Not a single vehicle but a secret network of maintained tunnels, hidden rail lines, safe houses, and improvised transport that moves people — refugees, escap…

A low-clearance tracked vehicle designed for Underworld traversal. Built from modified construction equipment or purpose-fabricated by Underworld communities…

In the deepest levels of the Underworld, where the water runs warm and bioluminescent fungi grow in sheets, some communities have cultivated massive fungal m…

A flat raft or canoe used to navigate the flooded tunnels and underground rivers beneath GLMZ. Some are simple wooden platforms with poles. Others are sealed…

A compact tunnel boring machine designed for creating passages through GLMZ's subsurface geology. The Tunneler chews through rock and reinforced concrete at …