K-Museum

At the end of the Dream Bridge on the Ariake side, there is a unique building resembling a fallen spaceship. It's one of the most notable works of architecture by Makoto Sei Watanabe, the talent behind such iconic buildings as Aoyama Technical College and Iidabashi Station.

It originally was designed to be one of the symbols of the World City Expo of 1996, but the event was canceled. Without the expo, development was dropped and the area was turned into a seaside park called Symbol Promenade Park.

But what's inside this spaceship of a building? From 1997 to 2001 it was home to a facility called the K-Museum. Run by the Tokyo Bureau of Port and Harbor, it exhibited the public utility system of the Ariake district, showcasing the pipes and electrical conduits that make the city run. Due to its somewhat tedious nature, the museum failed to attract visitors—frankly speaking, it was so unpopular it closed in just four years.

Indefinitely, that is, at least. The official statement from the K-Museum is that it is "temporarily closed," but its status is unclear as it's been closed for a much longer period than it was open. Perhaps it will reopen one day, but until then, the museum building remains an exhibit of its own.