The Hotel

The Survivors start on top of a hotel converted into a evacuation center, recently swarmed by the Infected. The Survivors witness the helicopters moving to a different location, and decide to follow them through the city. The Survivors become acquainted in an elevator and the Survivors must pry the elevator doors, making a loud screeching noise that summons the horde. Afterwards, they must fight through the remainder of the hotel, which is on fire.

Trivia

 * This hotel is featured in the Zombie Survival Guide trailer, when the Survivors are seeking to get to the evacuation center.
 * In the The Zombie Survival Guide the Survivors know each other at this point, although in-game they do not.
 * The hotel is on fire, which makes a horde scenario near the end difficult due to the screen being fogged up by smoke.
 * Its possible for a Jockey to ride you out of a window to your death.
 * The beginning of the level is almost identical to the beginning of the original Left 4 Dead in which the Survivors traveled through the city to roof of a living complex only to see their rescue chopper leave them behind.
 * Judging by the dialogue made in the elevator, it is assumed that the Survivors only met each other moments before the intro video ended.