Evacuation is a Blacklight: Retribution map set in an infected "Neo-Tokyo", after it has been evacuated.
This map was introduced with the Evacuation Update (0.991) in late 2012. The map is filled with sniper spots and walled defensive points around the map. If Weather is enabled, rains pours down in the outside areas of the map.
Much like Containment, these sniper spots can be used to your advantage for long range kills or patrolling in the center map will provide close to medium range engagements.