By train it's about 80 minutes away from Ikebukuro Station on the Red Arrow Limited Express to Chichibu city. By car, it can take from 90 minutes to two hours depending on your route and traffic. Going by car gives you the option to explore the various sites along the way, walks along the rivers, or stops at any of the many restaurants you'll find along the way.
Situated in a beautiful natural environment with a historical atmosphere, Chichibu has a lot to offer visitors regardless of the season. In the spring you can view the grounds carpeted by Shibazakura (pink moss) flowers, which look like sakura (cherry blossoms) in Hitsujiyama Park. If you go by car drive on back past the fields of blossoms and you'll find an area to relax and enjoy a picnic lunch.
Of course, during the sakura season, which lasts a bit longer in Chichibu as compared to Tokyo, you can see a nice variety of cherry trees and other flowers as you make your way along the highway.
In the summer you can take boat tours on the Arakawa (Ara River). This river runs from Saitama Prefecture to Tokyo. You'll have your choice of a gentle boat ride or you can raft your way down the river with some runs through the rapids. Boat rides are available from March through mid-December while rafting operates year round.
If you are fortunate enough to make your trip close to the May 5th Children's Day holiday in Japan be sure to visit the town of Kanna. There you can see hundreds of "koinobori," the traditional carp flags flown for this holiday. The display we saw, pictured here, is on the hillside by the Jinryu River. The town also holds a festival during the holiday weekend.
When we went we stopped for a short walk through the Onouchi Valley. Unfortunately, it was a very short walk as the old footbridge that crossed the river apparently was washed away some time ago. However, this new suspension bridge remains and offers a good view of the small waterfall in the valley. There are more interesting hikes and walks in the Chichibu region than this little valley, but it does have a small area jam packed with shakunage shrubs (Tsukushi rhododendron / part of the azalea family), which are usually in full bloom in the latter half of May or early June.
Take the Seibu line from Ikebukuro station in Tokyo to Seibu-Chichibu Station on the Seibu Chichibu Line.