Take a look at one of the most interesting cathedral’s you’ll ever see in Realmonte, Sicily. The cathedral is located inside a salt mine and can seat up to 800 people. The salt mine is the largest in Europe and spans over 62 miles of underground tunnels. I can imagine that having a cathedral would be a comforting thought for the miners that work in the salt mine. If you want to see some really cool works of artwork checkout these “Caves of Art” in New Mexico from artist Ra Paulette.