It's an entire museum devoted to old cellphones! The history and culture of mobile communication is the theme here, and visitors with an interest in Japanese industrial design can trace the evolution of mobile-phone fashions through the years. Exhibits span the decades from massive shoulder-mounted models (introduced in 1988), getting smaller and smaller up until the smart-phone era, after which they reverse course and generally get larger and larger.

Although it may not merit a special trip on its own for anyone but mobile-phone fanatics, this is one of several museums and other attractions in the Ryogoku area, and admission is free.