Just to set the record straight.....the St. Francis Riding Academy DID NOT BURN DOWN! The management decided in was losing patronage, and the property was worth more than they were making, so they sold the parcel on the SW corner of 7th Ave. and Cabrillo and the building was torn down in early 1958 after 54 years of service. The parcel was then developed by Safeway as a store with parking. The current store is the second of their markets on the site.
The original riding academy was built in 1904 as the San Francisco Riding Club. The primary patrons were the daughters of wealthyf San Franciscans. A listing from riding competitions reads like the Society Pages. Wealthy families often boarded their own horses at the Riding Club, and spent weekends riding the miles of bridle paths throughout Golden Gate Park, linked to Great Highway, Lake Merced and Sunset Boulevard.
In the 1906 earthquake, the north wall along Cabrillo St. (then called C St.) came down. All the brick structures in the Richmond District, like French Hospital and Maria Kipp Orphanage had similar damage. That is the only damage I have found associated with the St. Francis Riding Academy.
I grew up a block away from the Academy and knew it well. I have compiled photos and researched the story and plan to write an article for SF West History in the future.