The top of the Gateway Arch is really quite small with tiny windows. It looks bigger from the ground... There's just enough room up there for a few dozen people at once.

To get up there, you ride in "train" that's made up of 8 tiny spherical pods - each kind of like a tiny enclosed Ferris wheel capsule. Each has chairs for 5 people and just enough room to sit. I didn't get a picture a pod - the pace of entering/exiting was too quick. I think the pods are on some sort of track. Unlike a Ferris wheel, where gravity keeps the cars upright, a mechanical system keeps the pods upright in the arch as the train moves upwards. Every once in awhile it would adjust as the pod moved upwards. I was thinking it would be bad if the thing that keeps the pod upright fails...