The Lumilinna SnowCastle in Kemi, Finland is the biggest snow fort in the world. It opens from late January through mid April each year, featuring different architecture each year. The Snow Castle includes a hotel with 18 regular rooms, family rooms for groups up to five, and a honeymoon suite. The temperature hovers at a constant 23 degrees Fahrenheit. There's also an adventureland for kids, a theater, ice art gallery, restaurant and ice chapel.