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Mt. Asama & Usui Pass
One of the most popular places in Japan for people to escape the summer heat is in the area up around Karuizawa near Mt. Asama. One lovely August day I rode south from Haneo Station on the JR Agatsuma Line to Oniodashi Volcanic Park and then down through Karuizawa and descended down Usui Pass.
Gunma can be very hot in the summer time but, as you climb up into Asama Highlands, it cools down significantly. I rode on Hwy 146 south from Haneo Station. The road gradually gains altitude, about 600 meters in 15 km, to the turn off to Oniodashi.
The scenery is very pleasant. Thick green forests that open up into meadows with mountains in the background. Oniodashi Volcanic Park lies about 4 km west of 146. It features a rugged landscape of volcanic rocks deposited from the 1783 eruption of Mt. Asama.
It’s a really cool place providing splendid panoramic views of the Mt. Asama and valley below. There’s a trail that winds through the lava formations to a temple and observation deck in the center of it. I was there on a perfect-perfect blue-sky day.
I headed back to Hwy 146 and continued riding climbing up and over the shoulder of Mt Asama. The highest point is 1400 meters. After that you are treated to a long winding descent down into Karuizawa a beautiful mountain retreat town. It’s about 14 km from the turnoff to Oniodashi to Hwy 18, which runs east and west through the middle of the Karuizawa.
On the eastern edge of town Hwy 18 goes over Usui Pass and down into the Yokokawa area. Years ago, this road was the main road before a larger Hwy 18 bypass was built to the south to handle all the traffic coming to the area. It’s a delightful road with a short rise after leaving Karuizawa and then it descends 15 winding kilometers through the forest. It runs near the old railroad tracks which were abandoned when the Nagano Shinkasen began running.
Near the bottom is a famous brick railroad trestle called Megane Bashi (Eyeglasses Bridge) built in 1892. It served the railway line running between Yokokawa in Gunma and Karuizawa in Nagano until 1963. It has since been turned into a nice nature trail
As you continue your descent you come down into Yokokawa. Coming into town you get a nice view of the rocky crags running along the back of Mt. Miyogi just south of town. I had a splendid autumn ride/hike there which I’ve featured on the Mt. Miyogi Page. I finished my ride at Isobe Station a few km down the Usui River Valley from Yokokawa. I’ve really enjoyed my rides in Gunma. It is a beautiful place with a character all its own.
Mt. Asama & Usui Pass
