Built in 1929, the Maya Hotel is one of the most popular places for urban exploration in Japan. Hidden behind trees at the top of a mountain overlooking the city of Kobe, this Western style Art Deco haunt was used as a defence point in World War II (it was stocked with weapons in the 1940's to counteract U.S. invasions). The hotel was severely damaged in 1995 after an earthquake shattered the city, leaving the building in a state of disrepair. The owner decided to close up business permanently, leaving the building to rot and decay.
This is a tough one to access and you need to climb a steep trail lined with ropes to pull yourself up (gloves are very important here...). Finding the beginning of the trail is hard, but once you're on the right path, it takes about 40 minutes to an hour (depending on how fit you are). I was exhausted after the climb, but it was worth it - this haunting art deco building is really amazing (both internally and externally).