Room 91A is the middle San Juan period room (between 91C and B) created when 91W was divided. The room has an L shape, with maximum dimensions of 3.6 m north-south by 3.6 m east-west. Nineteen strata were identified in 91A including post-occupational fill, roof-fall, trash deposits, and upper and lower floors. Four features were recorded including two hearths, a milling bin, and a doorstep associated with the door connecting Rooms 91A and 91C. Based on the features present, Room 91A was used as a milling and habitation room, and for trash deposition subsequently. Ceramic data indicate usage into the late 1200s.