A NASA building, one of the largest constructions in the world, used to support space shuttle operations. It has a total capacity of 3 664 883 cubic m, equal to 3.75 times that of the Empire State Building, New York, and was originally built to assemble the Apollo–Saturn vehicles. The VAB is 160 m tall, 218 m long, and 158 m wide. It has a low bay area for maintenance and overhaul of the shuttle's main engine. The building has four high bays, each with a door 139 m high. Bays 1 and 3 are used to integrate and stack the complete shuttle vehicle, and 2 and 4 to check out and store the external tank, which is then attached to the shuttle waiting in 1 or 3. The completed stack, with solid rocket boosters, is put onto a mobile launcher platform and taken from the VAB to the launch pad by the crawler-transporter.

Within the Kennedy Space Center's gigantic Vehicle Assembly Building, space shuttle Discovery is mated with the external fuel tank and solid rocket booster assembly already mounted on the mobile launcher platform.

Credit: NASA