Other hazards include large yellow walls with doors that open and close.
The ruins include well-preserved Hellenistic walls with towers, of which five are still visible.
Some sections include concrete walls more than 20 feet high.
Landscape features include bridges and retaining walls constructed of stone.
These include underground gardens, walls of fire and walls of water.
Also, backdrops include walls, fences, and hedges which are intended to provide privacy.
Some do not include walls; in these, it is theoretically possible to fill the whole screen with Snake, and therefore "win" the game.
The facility includes 60ft overhung walls and a 15m official speed wall, both approved for competition.
The damage may include cracked walls, foundations and pipes.
The physical components of the envelope include the foundation, roof, walls, doors and windows.