From the outside, the design of the dome makes it seem smaller than it actually is. Its diameter is 384 feet, making it big enough to house a baseball field. It's 125 feet high, weighs 620 tons and is 110,000 square feet. Each of the 321 welded steel hexagons weighs roughly 2 tons.
Inside the dome is another dome, and the second one surrounds a control tower that is 80 feet high. The second dome, once covered with glass, served no purpose.
The building has changed hands and now is owned by KCS Rail.