The tower no longer has a roof and is what remains of a church that was demolished in 1539. Before that there were several other buildings on the site, going all the way back to medieval times. You can probably make out that tower originally had 3 stories, the floors of which along with the roof are also gone. This means that inside the tower you can look up and see the sky. There were some new-agey types hanging out at the base of the tower when we were there. This reflects the mystical and spiritual nature of the place, and Glastonbury town itself is full to the brim of shops selling all manner of hippy type clothes and books and stuff.