Mission Valley's morning mist still lingers in the background of this stunning photo of the ruins of Mission San Diego de Alcalá posted on the Vintage San Diego Facebook page by Tom Isom.  The shot looks west, or possibly southwest, with Point Loma at the very far right.  I-15 (or Ward Road, as I still sometimes call it) and Texas Street -- I believe -- are separating the three hills at the left. Wikipedia says Father Anthony Ubach began to restore the old Mission buildings in the 1880s.  Father Ubach died in 1907 and restoration work ceased until 1931, so this photo could actually have been taken around 1875.

What Tom Isom actually posted on Facebook was the Cabinet Card above.  I had never heard of a Cabinet Card.  Wikipedia says the cabinet card was a style of photograph that was widely used for photographic portraiture after 1870. It consisted of a thin photograph mounted on a card typically measuring 4 1/4 x 6 1/2 inches.  This isn't a portrait, so it may have actually been a plain old postcard.

(I use Wikipedia a lot, and send them $10.00 a month in appreciation)