The Hotel Rosslyn Annex is a historic building in Los Angeles, California built in 1923 at the corner of 5th and Main streets. The structure was designed by the firm Parkinson & Parkinson in the Beaux Arts style and listed on the National Register of Historic Places in 2013. The building is across the street from the original 800-room Rosslyn Hotel built in 1914. Designed as a twin, both were topped by mammoth glowing signs featuring the names surrounded by a heart, the shape acknowledging the Hart brothers who owned the hotels.