I'm not sure of the dimensions, but it is a decent sized enclosure. It has only been built for a few years. There is a walkway which runs above the side of the enclosure where you can see the viewing windows in my photo, and then there are viewing windows at ground level on the other sides. It is much better than the previous enclosure which was just a cage with some wooden structures inside. A cub was born (Kiska) last February.