Wakihonjin Okuya was the backup inn for high-ranking travelers when the main honjin was full or unsuitable. The present building is a handsome late-Edo house with dark beams, polished floors, hearth smoke, and the sort of cypress construction that makes Japanese domestic architecture feel both plain and rich.
It is one of the best interiors in Tsumago. Go inside rather than only photographing the street: the rooms make the old post-town hierarchy much easier to understand.