Here is a photo showing the extensive rockwork going inside of Everest. It looks like a lot of tunnels and caves and tight clearances in some areas.
http://photoalbums.wdwmagic.com/sho...941d151dcf5c7a14b621dfa&sort=1&cat=500&page=1
http://photoalbums.wdwmagic.com/sho...941d151dcf5c7a14b621dfa&sort=1&cat=500&page=1