[m4rtink]

The city of Beppu and especially it's Kannawa district is pretty much this & has been this way from Ancient times:

https://en.wikipedia.org/wiki/Beppu

It's really an almost surreal experience, with encrusted hot spring water pipes and steam everywhere in the district. Sometime you even need to be careful where you step to avoid to be scolded by steam coming up from the ground, likely due to overflow from the hot water boreholes flowing to the rainwater drainage system.

And it's not just the modern hot water boreholes they use to supply the hot spring baths & other users. One time we even saw a traffic code & couple sandbags placed on a random hillside next to the road, as there was steam escaping out of it. :D