Indoor riding halls (or arenas) in Europe are built a lot differently than most of them in the US, at least the ones I have seen in Eastern PA and NJ.  We tend to build whatever is the least expensive.  Whereas in Europe they build something that is very attractive and will last as seen on the photo to the left. 

This one is probably the most beautiful riding hall I had seen while in Warendorf, Germany last fall. I was in Deutschland for the World Equestrian Games in Aachen and ventured up north on a side trip with a few colleauges.  This indoor arena is located at the DOKR which is the German Olympic Equestrian Committee.