Mount Unzen (ë_ÉňŐx, Unzendake) is an active volcano at the center of the Shimabara Peninsula, which has erupted several times in the last few hundred years with deadly results. The most recent eruption occurred from 1990-1995 when pyroclastic flows (superheated volcanic gases) and mudslides raced down the mountain towards Shimabara City, destroying buildings along the way. One of the pyroclastic flows killed several scientists, journalists and their drivers who tried to document the event.
Despite its reputation for death and destruction, Mount Unzen was recognized in 1934 for its natural beauty and made part of the Unzen Amakusa National Park, one of the first national parks in Japan. In spring Unzen's slopes are covered in pink azaleas, and summers on the mountain are mild and green. Also, due to its high elevation, Mount Unzen is one of the relatively few autumn color spots in Kyushu. The season usually peaks from late October to mid November.
Visitors to Mount Unzen can drive as far as Nita-toge Pass (along a one-way, 100 yen toll road), from where the Unzen Ropeway leads part way up the mountain slope. The lower and upper ropeway stations have observation decks with views over the surrounding mountains and the Ariake Sea all the way to Kumamoto Prefecture on a clear day. The lower ropeway station has a large parking lot, shops, restaurants and the trailheads of hiking trails that lead up the mountain.
A popular hiking route leads from the upper ropeway station along the ridge to Fugendake (1359 m), the highest peak that you can climb to. From there you can look out just a few hundred meters away to the smoking summit of Heisei Shinzan (1486 m), the highest and newest peak on Mount Unzen that was formed when the volcano last erupted. It takes about one hour to hike between the upper ropeway station and Fugendake, plus an additional 20-40 minutes if you bypass the ropeway.
A little ways down from the Nita-toge Pass lies Unzen Onsen, a hot spring town that has nice baths and interesting hot spring fields. The town provides accommodation as well as convenient access from Shimabara City, Nagasaki and Fukuoka, making it a good base for climbing Mount Unzen.
Further down the mountain toward Shimabara is the Heisei Shinzan Nature Center, a small museum with displays about the mountain, the effects of the disaster, and what is being done to monitor the mountain to prevent future catastrophe. A small network of walking trails leads around the center to viewpoints from where you can look out at the mountain. Note that the center is relatively far away and not directly accessible from Unzen Onsen. It must instead be approached from Shimabara City.
Unzen Onsen is directly connected by bus to Shimabara (50 minutes, 850 yen, hourly departures), Isahaya (90 minutes, 1400 yen, hourly departures) and Nagasaki (100 minutes, 1850 yen, infrequent departures). Public transportation between the town and Nita-toge pass is very inconvenient. There is a scheduled "shared taxi" service (430 yen one way) that departs three times per day but requires advance reservations. Alternatively, you can take a taxi (about 1800 yen) or walk (about 1 hour) to the lower ropeway station.
The Heisei Shinzan Nature Center is not directly accessible from the mountain top and must instead be approached from the coast. An infrequent shuttle bus operates from Shimabara Port, looping around to Shimabara Station and the nature center along the way before returning to the port. The one way trip takes about 30 minutes from either the port or the station.
A rental car is recommended for a visit to Mount Unzen and the nature center.
Departures every 4 to 8 minutes