Okutama, easy access and abundant nature in western Tokyo.

Okutama Town is located on the western edge of Tokyo. It is 40 miles west and two-hour train ride from Tokyo Station via Shinjuku and surrounded by green mountains but certainly within Tokyo Prefecture. It is a part of Chichibu Tama Kai National Park but major local tourist attractions are within short distances from stations of JR Okutama Lines or frequent local bus services are operated.

Yamano Furusato Village is a leisure facility that offers a variety of activities such as guided walking tours, yoga lessons and soba buckwheat noodles making. Soba making experience includes ingredients, tools and instructions, and at the end of the lesson, you can eat soba noodles that you have made by yourself. The programs are called "Okutama forest therapy", which examine your body data before and after the programs, which show the effect of the programs how you are released from the stress in your daily life referring to the statics. It takes about 30 minutes from Okutama Station by a local bus or a free pickup bus (reservation required),
http://www.yamafuru.com/
http://okutama-therapy.com/

Hatonosu Ravine is the upstream of Tama River where you can enjoy walking along the stream starting from the train station. Okutama River International Trout Fishing Spot offers rainbow trout fishing, without any preparation for a fishing rod, bait and everything is ready here, where even beginners are able to catch several fishes. Nippara Limestone cave is one of the longest caves in Japan which visitors can walk inside and it show you fantastic scenery (so chilly inside even during summer).
http://www.tachikawaonline.jp/walk/hatonosu.htm
http://www.okutamas.co.jp/kokusai/
http://www.nippara.com/nippara/syounyuudou/syounyuudou.html

Onsen hot spring is available at public bath houses like Moegi-no-yu. If you are affordable for an overnight trip, Hatonosuso is your good option. The hotel was renovated in 2015 and offers Onsen hot spring bath and Italian cuisine cooked with organic local vegetables for dinner and breakfast.
http://www.okutamas.co.jp/hatonosu/

I have been living in Tokyo for decades but never be able to find other places surrounded by nature in a such convenient distance where you can access by trains easily. The train fare from Tokyo Station is only 1,250 yen and no prior seat reservation and no additional charge are necessary so you can make up your mind for going out of central Tokyo if you are in the mode for excursion in the morning. JR East Railway operates special train "Ozashiki Mitake Seiryu Go" from Kawasaki to OKutama as well on Aug. 13, 14, 20 and 21, 2016 with specially designed vehicles with drawing rooms inside.
https://www.tetsudo.com/event/15095/