World's deepest hotel room is inside 65 mn yr old cave in US
The Grand Canyon Caverns in Arizona, US, provides a suite that is claimed to be the 'the oldest, darkest, deepest, quietest, and largest suite room in the world'. The room, 220 feet below ground, is located in caves that are over 65 million years old. It can accommodate up to six people and features an attached bathroom, among other amenities.