Room 91W is an original Chacoan room located in the central sector of Salmon Pueblo, west of the Tower Kiva (Room 64W). It measures 5.8 x 3.6 m. The room was built during the initial Chacoan construction episode around 1090 and subsequently modified by the San Juan occupants. This later activity resulted in the creation of three room spaces (91A, B, and C). The 91D designation was used across the Room 91W area for a series of strata that were believed to be San Juan in origin. However, this use occurred below the San Juan dividing wall so it properly belongs to the original Chacoan Room 91W (but was not recorded that way). Of the 40 strata recorded in Room 91W, most were related to trash mounds that accrued in the room over time as refused was put into the room. Other strata include post-occupational units, floor units, and construction related fill. Room 91W contained 8 features including four doorways, two vent windows, a macaw, and one recorded latilla beam. Tree-ring dates indicate construction around 1090 and the ceramic assemblage indicates use into the late 1200s.