The "hot spring resort" has its roots in ancient Japan.

The "hot spring resort" has its roots in ancient Japan.
In areas with bountiful hot springs, people would come and stay up to 3 weeks to relieve pent up stress and pain from agricultural work and such.
The flow of information was limited back then, so people who gathered from afar, as well as the locals, took this opportunity to exchange skills and knowledge, and furthermore revitalize themselves for their next laborious task.
One could say that generally healthy and active lifestyles revolved around onsen for people long ago.

日本にはかつて湯治という優れた習慣があった。
温泉地に2〜3週間滞在して、農作業などでたまった疲れや
ストレスを解消。情報が少ない時代だったので、湯治客同士や地元の人たちと知識や情報を交換したり、次の農作業へ体力を充電したりする意味をもっていた。いわば温泉療法という形で健康づくりを行っていた先人たちの生活の知恵です。