Yamagata Prefectural Sports Park

A prefectural sports park in Tendo, run by Montedio Yamagata. Alongside the arenas, martial arts halls, training room and a training lodge (gasshukusho, 合宿所), the gym building has a bath filled with onsen water. It is an ancillary of the sports facilities rather than a bathhouse in its own right, and the sources do not say whether outside visitors can walk in, so check with the park first.