Metamorphic rocks "tatami rocks" at Nagatoro

Designated as a national Natural Monument, the Tatami Rocks, are so called (Nagatoro Iwadadami 長瀞の岩畳) because from the aerial view, the schist terraces or “tatami stones” look like tatami mats.

Yakata-bune docked at the Nagatoro Riverside (Wikipedia photo)

Riding down the river in a yakata-bune boat is said to one of the best ways to view the Nagatoro Red Wall (precipitous cliffs also known as Chichibu Sekiheki, named after the famous Red Wall cliffs of China) that flanks one side of the river gorge. The Nagatoro River Gorge area is a terrific place to study geology – it is part of a 5 kilometer rock-bed and the area is full of exposed terraces of chlorite schist, a type of crystalline schist. Standard textbook or geography/geology fieldtrip activity is to study schist formations and there are many types of schist formations to be found in the area — they are collectively known as the Nagatoro metamorphic rocks.

Cruising down Nagatoro river is a great way to study the rocks (Wipedia photo)

If on a fossil-hunting or geological fieldtrip, you might like to combine your activity with a visit to the Saitama Prefectural Museum of Natural History which is a terrific museum for learning about fossils, minerals and geology of Saitama. Nagatoro is known for their prehistoric fossils of the Paleoparadoxia Tabadai a good collection of which may be seen on display at the museum.

Aside from fossil-hunting, you can either bring your kids on a yakata-bune boat ride or older more adventurous ones can go river rafting or kayaking on the rapids on Nagatoro River. The Nagatoro River is famous for its rapids and whitewater rafting and boating facilities and the town is situated in a prefectural nature park.

The younger kids will all want to ride the Paleo Express, an authentic steam locomotive for the old-fashioned round-trip journey between Kumagaya and Mitsumine-guchi stations, complete with uniformed conductors and ear-piercing whistles…like in the Polar Express.

Nearby the Nagatoro river, you can also take the cable car to the peak of Mount Hodo where at the observation deck you can catch a great view of Chichibu mountains.

Source references and further resources:

Rivers and rails in Saitama (Tokyo Families Magazine)

Rock Tatami of Nagatoro Great photos at Pavel Holoborodko’s and Dirk’s Travel Notes – Nagatoro blogsites.

Nagatoro River Area (Saitama Tourism)

See IAC’s photo gallery of river rafting trip on Nagatoro river

Secret Japan recommends using Montbell Club / Montbell Outdoor Challenge or M.O.C. for short for river rafting and kayaking tours and activities.

Another well-known (to locals) whitewater adventure facility is  Outdoor Center Nagatoro. They service customers who go want to go kayaking, “river-boogie,” canyoning, mountain biking and more. English-speaking customers are fine by their staff although their website is only in Japanese.
Access: (Train) Tobu-Tojo Line from Ikebukuro for Yorii connecting through Ogawa. Chichibu Line from Yorii to Kami-Nagatoro Station. Walk straight through the ticket gate and left at the river. Located inside the River Park Kami-Nagatoro RV Park. (Car) Exit the Kanetsu Expressway at the Hanazono I.C. and head for Yorii. Left at the 7-Eleven after the Nagatoro Station crossing, followed by a right at the river. The meeting spot is 200 meters down river on the right.
Phone: (0494) 66-4165 / 0120-66-4162 (toll-free)
Email: info@outdoornagatoro.com
Website: www.outdoornagatoro.com

Sunburst Adventures is recommended on Travel Channel by Stephen Lebovits (who writes for Tokyo Families Magazine) – “Located just 2 hours outside Tokyo, their 6-kilometer river-rafting trip is safe and fun for the whole family.”

824-1 Saitama Nagatoro Cho, Chichibu Gun, Tokyo Japan 369-1305 Phone: 81 4 9466 382

Map of Nagatoro area

Listing of Campsites at Nagatoro (By Outdoor Japan)

Sunburst

Nagatoro Camp There are two riverside campsites, one for tents, the other for 4WDs and caravans. Bungalows and cabins available from 4,000 yen to 25,000 yen. Phone: 0494-66-0640 for reservations. Access: Take the Takasaki line from Ueno to Kumagaya, then hop on Chichibu line to Nogami. Activities: Swimming, fishing, canoeing or hiking.