People often confuse a sentō with an onsen. The difference is actually quite simple.

Both are bathhouses. An onsen is defined by the water. A sentō is defined by the building.

A sentō is a public bathhouse, traditionally visited because many homes didn't have their own bath. Today, almost every home does, yet thousands of sentō are still in operation across Japan. Most use heated tap water rather than natural hot spring water, although some are supplied by onsen water too.

The bath itself isn't there to remove dirt. Everyone washes thoroughly before getting in, so the water is shared respectfully by everyone using it. The soak comes afterwards.

No two sentō are quite the same. Some have timber lockers, vintage weighing scales and hand-painted Mount Fuji murals, creating the feeling of bathing beneath an open sky even in the middle of a busy city. Others are strikingly modern. What they share are the rituals that make a Japanese bathhouse feel unmistakably Japanese.

At one end of the spectrum you'll find small neighbourhood bathhouses. They're often quiet places where regulars stop by after work to soak, chat with familiar faces, or simply enjoy half an hour of peace before heading home.

At the other are super sentō: much larger bathing complexes with multiple indoor and outdoor baths, saunas, cold plunge pools, restaurants and relaxation spaces. Many stay open late into the evening, and some welcome guests around the clock.

Whether you visit a quiet local sentō or a modern bathing complex, you'll notice the same sense of shared space. Without uniforms, jewellery or expensive clothes, everyone enters the water in much the same way. In Japan, that shared experience has long been seen as one of the quiet strengths of communal bathing.

Yū Bathhouse is inspired by the rituals and atmosphere of Japan's great bathhouses.

Follow our journey as we work towards opening our first location.