Kusatsu Onsen
- Information on Kusatsu Onsen, one of the better known hot spring resort towns in Japan, including ryokan (guest house) information and a history of this particular hot spring.
- http://www.kusatsu-onsen.org

OnsenExpress
- Helping travellers to obtain information on some of Japan's hot springs and accompanying ryokan (Japanese style guest houses).
- http://www.onsenexpress.com

Wikipedia: Onsen
- A description of onsen, why they exist and what the Japanese use the water for.
- http://en.wikipedia.org/wiki/Onsen

Secret Onsen
- A database containing more than 100 onsen all around Japan with maps, pictures and rating. Mostly focusing on rotenburo (ouside baths) and konyoku (mixed baths).
- http://www.secret-japan.com/onsen/

SentoGuide
- A guide to sento, Japanese public baths, including contact, location a facilities information for listed baths.
- http://www.sentoguide.com

Ten Most Unique Sento
- The ten most unique sento (public baths) in Japan.
- http://park.org/Japan/Hitachi/nippon/sento/e/sent2005.htm

Fukuoka Onsen
- A guide to hot springs in Fukuoka Prefecture.
- http://www.fukuoka-tourism.net/e/hotspring.html

Hot Spring Index
- Nationwide guide to hot springs across Japan.
- http://www2.gol.com/users/jolsen/onsen/

Onsen Map
- Stories and descriptions of hot springs in northern Japan.
- http://www.east.co.jp/oyu/english/

Onsens of Japan
- An English guide to onsen (hot springs) in Japan, grouped by region.
- http://www.myguidejapan.com/

East Japan Day Trip Onsen Michelin
- Hot springs within one day's drive from Tokyo.
- http://www.asahi-net.or.jp/~ue3t-cb/index_e/index_e.htm