Left 4 Dead/The Apartments

This level starts off at the top of the apartment building. To complete the level, you need to travel to the base of the apartment and cross a few city blocks. The exit is recognizable by a staircase nearby a secure car.

Paths
At the top of the apartment, you can either enter using the staircase or through the breakable skylight.

When approaching the exit, you can either follow the street directly, or take a longer route behind a heavy truck and fence.

Shortcuts
At the beginning, you start at the roof - behind the players is the alley where you normally exit the building. Advanced players can skip the apartments by jumping onto the air-conditioning unit; this inflicts damage, but skips past a portion of the level. If you miss the jump, it's instant death.

Traps

 * One car alarm, located near the exit.