People have been familiar with bathing from long ago in Japan, due to its location in a high temperature and high humidity subtropical region. As the bathtub’s finest material, there is a Hinoki, Japanese cypress, with a beautiful tint, smooth touch and fine fragrant. However, its maintenance takes much care and time, which makes it difficult to use it in ordinary households. This bathtub makes it possible to enjoy the Hinoki scent and smooth touch with ease of maintenance by using green Towada stone as the surface material of the unit bus and Kiso cypress as the frame. The contributions to the bathing culture and to the local economy via the use of domestic natural resources were highly appraised.