Room 123W is an original Chacoan room located in the southeast sector of Salmon Pueblo. It measures 5 x 3.1 m and was subdivided late in the San Juan occupation into Rooms 123A and 123B. Room 123W had a Chacoan floor with evidence of considerable San Juan intrusion for burial purposes. Twenty-eight strata were identified in 123W including structured trash, occupational fill, feature fill, construction debris, preconstruction layers, and several strata identified as structural floors. Ten features were recorded in Room 123W. Chacoan doorways built in the east and west walls were reused by the later San Juan occupants. Other features included a storage pit of Chacoan origin, two other pits, and five Chacoan age hearths. No features of purely San Juan origin were recorded in the room. Based on the architectural style, stratigraphy, and ceramic assemblage, Room 123W was likely constructed during the original Chacoan episode around 1090.