Ashio Copper Mine Tourism (Ashio Dozan Kanko)
After mining operations halted, one section was opened to the public in the form of a historical museum. Visitors can ride a trolley train to the entrance of the pit, and walk underground from there. Dioramas with life-size figures show how mining was done in the old days, as well as the processes required for turning raw ore into purified copper. The site is a 10-minute walk from Tsudo Station on the Watarase Keikoku Railway.
Ashio Environmental Learning Center
This facility is run by Grow Green in Ashio, a non-profit organization. Displays explain the natural environment around Ashio and the extent of the pollution damage to the mountainsides, which became barren due to the toxic gases emitted from the copper refining plant. This NPO is also engaged in a program of reforestation, which aims to plant 1 million trees on the surrounding slopes. Prior reservations are required if you want to participate in the tree planting.
Watarase Retarding Basin (Watarase Yusuichi)
This huge reservoir covering 33 square kilometers was created for storing water, controlling floods and purifying toxins from the polluted water that flowed downstream from the Ashio copper mine. A cycling road has been built, as well as a path where it is safe for visitors to enter. Wild birds can be seen here throughout the year. Visitors can also view the area from hot-air balloon tours, which start early in the morning.
To reach Ashio, it takes 50 minutes by local bus from Nikko (either Tobu Nikko Line or JR Nikko Line station). You can get there on Watarase Keikoku Railway. The closest station to the Watarase Retarding Basin is Fujioka, on the Tobu Nikko line.