Vegetarian's Japan Guide

Agatsuma Gorge: The Most Amazing Gorge Close to Tokyo

Agatsuma Gorge (吾妻渓谷) is a must-visit scenic spot in Kawarayu Onsen. The stunning gorge tucked away in the mountains of Gunma is a designed National Place of Scenery Beauty. Especially during the autumn leaves and fresh green seasons, the sheer valley is so beautiful buried amongst the red and light green trees.

The 2.5km gorge starts from the Fureai Bridge (ふれあい大橋) to Yamba Dam. It is thought that Agatsuma Gorge was formed by the continuous erosion of river water of the terrain, created by the lava spewed out from surrounding volcanos. While a quarter of Agatsuma Gorge is a part of the Yamba Dam now, at least we still have three-quarters of the gorge thanks to fierce protests from the locals.

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The Best Time to Visit Agatsuma Gorge

  • Around mid-April, Agatsuma Gorge is colored by azalea flowers.
  • Agatsuma Gorge’s light green season is in May.
  • For autumn foliage, visit Agatsuma Gorge from late October to early November.

How to Get to Agatsuma Gorge

Tip: Shuttle buses operated by Kanetsu Bus connect JR Iwashima Station and Roadside Station Agatsumakyo daily during the fall foliage season from late October to mid-November and possibly from the end of April to early May.

How to Explore Agatsuma Gorge

There are a few hiking trails at Agatsuma Gorge. Depending on your fitness level, you can embark on the well-maintained flat promenade or the unpaved mountain trail.

Although it is only in Japanese, you can use the Agatsuma Gorge Hiking Course Map in conjunction with Google Maps to plan your visit. Note that the trails are closed during winter for your safety.

  • The green line marks the unpaved hiking course.
  • The red line marks the promenade.
  • The blue and white line marked the abandoned train track, now a rail bicycle track called Agaddan (アガッタン). The track goes through the Tarusawa Tunnel, allowing you to examine Japan’s shortest train tunnel in detail.
    • If you would like to experience the rail bike, it is best to reserve, especially during the light green and fall foliage season.
    • For more information, refer to the official website HERE.
  • A return trip from Junisawa Parking Lot (十二沢パーキング) takes around 120 minutes.
  • A return trip from Roadside Station Agatsumakyo (道の駅 あがつま峡) takes around 135 minutes.

Directory signs in Japanese are placed throughout the tracking courses. Remember to download the map on your phone to match the Japanese on the signs with the scenic spot’s English name.

Saruhashi Bridge (猿橋)

Around 2km from the Roadside Station Agatsumakyo, Saruhashi Bridge is the starting point of Agatsuma Gorge’s hiking trail.

The bridge was first built in the Edo period. Due to natural disasters, the bridge was repeatedly restored. The current bridge was completed in 2017.

Whether you plan to drive or not, stop by Junisawa Parking Lot (十二沢パーキング) for the lookout next to it.

When you are on Saruhashi Bridge, look up to Agatsuma Gorge’s upstream for the Shiraginu Falls (白絹の滝). It is a silk-thin waterfall that cascades down and empties into the Azuma River.

Byōbuiwa (屏風岩)

Another scenic spot that we want to introduce is the Byōbuiwa. It is formed by six 200-meter-tall rocks lined up like a folding screen. In addition to looking up, if you look down to the lower part of the rocks, you will find the Tarusawa Tunnel, where the old train track goes through.

Tarusawa Tunnel (樽沢トンネル)

Tarusawa Tunnel was a part of the old JR Agatsuma Line that ran along the Agatsuma Valley. Its length is only 7.2 meters, so it was Japan’s shortest rail tunnel. While you can’t enter the tunnel by foot, taking a peak from the promenade of this tunnel (completed in 1946) is possible. If you want to get a bird’s-eye view of the entire area, we recommend viewing it from Junizawa Parking.

The tunnel’s guide board and benches are placed next to the shafts. Even if you aren’t a rail buff, it is a nice little gem to stop by for a mysterious, natural vibe!

Hacchōkuragari (八丁暗がり) and Shikatobi Bridge (鹿飛橋)

Walking on the hiking trail, there are various scenic spots lined one after another.

For example, Shikatobi Bridge’s vermillion guard rail vividly contrasts the surrounding nature. The part of the gorge is called Hacchōkuragari.

Ⓒ 群馬県観光物産国際協会

For around 900 meters, the distance between the banks is the shortest, but the gorge has a height of 50 meters, forming a steep V-shape. The distance can be as short as only two to three meters so that deer can jump across the gorge. This is why the red bridge here is called Shikatobi.

Roadside Station Agatsumakyo (道の駅 あがつま峡)

After enjoying the beauty of the Agatsuma Gorge, how about stopping by the Roadside Station Agatsumakyo to rejuvenate? In addition to a farmer’s market, there is a tourist information counter, a restaurant, a park with a free foot spa, and a public bathhouse called Tengū no Yu (天狗の湯). The best thing is there is a private bath with indoor and outdoor onsen tubs that anyone can rent!

Note that the free foot spa in the park is closed during winter.

Tip: The two toilet facilities and the parking lot are open 24/7.

About Tengū no Yu

  • Tengū no Yu is open daily from 10 am to 9 pm except for the 2nd Tuesday of the month.
    • The last admission is at 8:30 pm.
  • The admission fee is
    • 420 yen for adults
    • 210 yen for children from 3 to elementary school students.
  • The private bath can be rented out at 10:30 am, 1 pm, 3 pm, and 6 pm for 2 hours.
    • The cost is 2,100 yen per use.
    • You can call +81-279-67-2683 to reserve the private bath.
  • Coin-operated lockers costing 100 per use are available.
  • Food and drinks can be brought into the bathhouse, but please refrain from bringing in alcohol.
  • Shampoo and body soap are available, but towels aren’t provided for free.

Roadside Station Agatsumakyo’s Opening Hours and Access Information

  • Roadside Station Agatsumakyo is a 40-minute walk from JR Iwashima Station (岩島駅).
  • You can take the Tengunoyu Loop Line from either JR Gumma-Haramachi Station (群馬原町駅) or Iwashima Station (岩島駅) and get off at Tengu no Yu (天狗の湯).
    • Refer to HERE and scroll down to Tengunoyu Loop Line (天狗の湯循環線) and click “時刻表” for the service’s timetable.

Discover Other Attractions in Kawarayu Onsen

Click the photo for more tourist spots in Kawarayu Onsen!

As you might know already, Agatsuma Gorge isn’t the only attraction in Kawarayu Onsen. The hot spring town tucked in Gunma Prefecture‘s beautiful mountains is a great destination to enjoy a range of outdoor activities besides the hot spring. In addition to hiking and watersport activities, you can even do bungy jumping!

For more information, refer to our article on Kawarayu Onsen!