From The TimeSplitters Wiki

Mars Prison
Size	Large
Location	On Mars
Climate	None
Unlockable	Unlocked by Default
Recommended Bots	Lazarus Mumble Angel Forge Ghengis Kant Lt. Black Prison Officer Mordecai Jones Comrade Papadov INSETICK SD/12 Ivor Baddic Time Assassin
Recommended Weapons	Sci-Fi Handgun Plasma Autorifle Sci-Fi Sniper Rocket Launcher Plasma Grenades Timed Mines

Mars Prison is set on Mars. It seems a large map when compared to the other maps on TimeSplitters Future Perfect. This level is playable on the Assault Mode