There was a room on Venus built into the cliffside that you could go into, but it was totally empty. Didn't think much of it until I tried to ride my Sparrow in to check for a chest or something. For whatever weird reason, once you got about half way through the room, your Sparrow just falls to the ground and refuses to move forward. It's like it's got magnets on the bottom and the floor is made out of metal. Pretty sure they've closed off that room with a fancy fog wall now, but was neat while it lasted.