Nu Land Sagami-yu

Sitting not far from the border with Kanagawa Prefecture, this Zoshiki bathhouse boasts a restaurant, karaoke room, massage service, relaxation chairs and small rooftop garden. If you're just looking to take a long soak, there's a range of tubs to choose from, including an outdoor rotenburo and an indoor onsen bath that uses Ota-ku's distinctive kuroyu black water. These are all available for a basic charge of ¥450, though you'll have to pay extra if you want to use the sauna and other facilites.