At Nagako-ken’s eastern edge, on the slopes of Asama-yama, is the ritzy resort of Karuizawa (軽井沢) where Crown Prince Akihito (now the emperor) met his future wife, Michiko, on the tennis courts in the 1950s, and where John Lennon and Yoko Ono vacationed in the 1960s and 1970s. Decades of such superstar patronage have lent this small town a fashionable reputation, and the place can get very hectic in summer as Tokyoites descend to relax in the cooler mountain air and spend up a storm at the giant outlet mall and tacky tourist-shop strip either side of the main station. It’s pretty easy to escape this commercial frenzy and enjoy Karuizawa’s natural tranquillity on easy trekking and cycling routes into the forested hills dotted with charming wooden villas and heritage buildings.
The scenic part of town begins in Kyū-Karuizawa (旧軽井沢), about 1km north of the station. Work your way past the tourists jamming the pedestrianized, tacky shopping street dubbed “Little Ginza”, to emerge into a forest. Here you’ll find the quaint wooden Anglican Chapel, fronted by a bust of the Canadian missionary Alexander Croft Shaw, who helped popularize the area as a retreat. A short walk southeast is the historic Mampei Hotel, which has a small museum of its memorabilia.
Heading northwest along the main road, Mikasa-dōri, it’s a pleasant 2km cycle ride or hike up to the secluded Old Mikasa Hotel (旧三笠ホテル), an elegant wooden building dating from 1906 that’s now a national monument. Follow the road north from here, past the camping ground, to Kose (小瀬) where a 10km hike to the scenic Shiraito Falls (白糸の滝) starts, and onwards west to Mine-no-chaya (峰の茶屋) from where you can take a bus back to Karuizawa Station.
A 6km pedal west of Karuizawa is Naka-Karuizawa (中軽井沢), another beautiful area for cycling, hiking and relaxing. The main focus is the Hoshino area where you’ll find the luxury resort hotel Hoshinoya, an excellent onsen, Tonbo-no-yu (トンボの湯), a forest of chestnut and larch trees where you can take guided nature tours and a stylish, low-key shopping and dining complex, Harunire Terrace. If you don’t feel like cycling, a free bus runs here from the south side of Karuizawa Station; enquire at the tourist information office about the schedule.
Looming ominously over Karuizawa is 2568m Asama-yama (浅間山), Japan’s highest triple-cratered active volcano, which last erupted in 2004. The closest you can get to the crater is on its north side at Onioshidashien (鬼押出し園), 21km from Karuizawa. Onioshidashien was the scene of a cataclysmic eruption on August 5, 1783, when ashes from the blowout were said to have darkened the sky as far as Europe, and a 7km-wide lava flow swept away Kanbara village. When the lava cooled it solidified into an extraordinary landscape of black boulders and bizarre rock shapes, where alpine plants now sprout and across which twisting pathways have been laid. To see the scale of the place, head up to the observation floor in the gift shop and restaurant complex at the entrance. Most of the crowds head for the central temple, Kannon-dō, standing on a raised red platform amid the black rocks, but you can easily escape them by continuing past to the quieter area behind.