Made for putting together huge spacecraft, NASA’s Vehicle Assembly Building (or VAB) is one of the world’s largest buildings. At 525 feet, it’s way taller than the Statue of Liberty (a mere 305 feet), and in terms of volume, it’s equal to 3.75 Empire State Buildings.

Completed in 1966 at the Kennedy Space Center in Florida, the VAB was originally called the Vertical Assembly Building, because its purpose was to allow the Apollo program’s Saturn V rockets to be “stacked,” or put together in an upright position. Those huge rockets needed a huge space: the VAB covers eight acres, or just under eight football fields!

The entrances to the building’s four construction bays are 456 feet high, making them the world’s largest doors. The VAB’s interior space is so massive that, on very humid days, NASA employees have seen rain clouds forming on the ceiling!

The VAB was renamed in the late 1970s, when the space shuttle program began. It was refitted and updated to be used for the construction and assembly of the shuttle orbiters, their fuel tanks, and their solid rocket boosters.

When the space shuttle program ended in 2011, the VAB was modified once more, this time so crews could work on multiple launch vehicles, including the new Space Launch System heavy-lift rocket and Orion spacecraft. They even work on commercial rockets there, because NASA partners with private companies on some projects.

Not surprisingly, this refurbishment was a massive undertaking: Work platforms the size of whole buildings had to be removed from the bays and demolished, and many updates were needed, including modernizing the fire-suppression equipment and other safety systems. To make room for state-of-the-art command and power systems, workers took out more than 150 miles of outdated cables!