I have a photo of how it was set up but at that point I only had a smaller shelf over it at the back, which you can hardly see on the photo, not at the front/right. It was one of the lava ledges. I also later removed the long bendy bridge as the hamster didn't like it as it wobbled (and it also broke pretty quickly!).
I then later added this roof tube - leading from the flat roof to the sputnik - it meant the hamster started using the sputnik and used to hang out in it
If you put some bedding in it.
Attachment 53450
Attachment 53451