Kumamoto Castle was constructed in 1607 and was the site of Japan's last civil war in 1877. Most of the present castle buildings are reconstructions from the 1960s. Mt. Aso, located in Kumamoto Prefecture, is one of the largest active volcanoes in Japan. The low-floor tram system introduced in Kumamoto in 1997 was the first in Japan to be accessible for the elderly and disabled. Suizenji Park in Kumamoto City is a strolling garden built in the 1630s, modeled after scenic spots along the Tokaido road, and features ponds, hills, and plantings.