Kaisei-yu

Soak in black, mineral-rich hot spring water at this comfy sento (public bathhouse), located on the north side of Kamata Station. Renovated in 2011, Kaisei-yu features a cool aquarium right in front of the baths, so you can watch the fish swim around while you wash away the tiredness of a long day out. In addition to the kuro-yu baths, there's also a moisturising 'white bath' and a jet pool.