We recently visited the deepest station in Japan. Doai Station is a passenger railway station in the town of Minakami, Gunma, Japan, operated by the East Japan Railway Company (JR East). It's 70m (230 ft) deep, and if you want to use the station, it'll take you 10 minutes just to get down to the tracks... let alone come back up! There are no escalators or lifts. Oh, and apparently, it's haunted. So, of course, this place has been on my 'want to go' list for a while.
It was definitely worth visiting in my opinion. It was very spooky and made for some great photographs. We visited in summer, so it was super hot outside, and once you're down at the bottom, it's actually pretty cold. Apparently, it has 19 daily passengers as well... I can't imagine doing that every day!