Yuuki-an, also known as the Osawa-ya Tea House, is a contemporary architectural work completed in 1988 in Ikaho, Gunma Prefecture. Designed by renowned architect Hiroshi Hara and Atelier Phi Architectural Institute, this structure exemplifies innovative modern design principles while honoring traditional Japanese aesthetics. Originally conceived as a tea room, the building now serves as a gallery and art project space, showcasing the architect's distinctive approach to blending cultural heritage with contemporary spatial concepts. Its thoughtful integration into the natural landscape of Mizusawa makes it a significant example of late twentieth-century Japanese architecture worthy of architectural study and appreciation.