This attraction is a mirror maze. As other reviewers have stated, you're provided with plastic gloves in order to keep from fingerprinting the mirrors. It can get confusing in the maze and you really do need to feel your way along in order to keep from walking into a mirror wall. It is fairly well lit inside. If your group wants to stay together it's a good idea to keep in physical contact with each other. Some areas open up, it's not just a "hallway passage" all the way thru. I would allow 10-15 minutes max. depending on how "lost" you want to get or stay inside. I can't verify that more than one entry is allowed per day, we weren't given that option when we purchased our tickets.
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