That round thing in the lower left of the photo? It is a gun battery. The Point Loma penninsula provides a natural protective barrier to San Diego. The area was declared a military preserve in 1852. Fort Rosecrans was dedicated in 1899 and a series of batteries were constructed to enhance coastal defenses. Battery Ashburn, not this particular one, housed two massive 16 inch guns capable of firing 2,300 pound shells nearly 30 miles out to sea! That's kinda like throwing a Toyota Prius from Escondido to San Diego!

The assistant keeper lived in the building attached to the lighthouse while the principal keeper lived in a separate house. The keepers used the lighthouse, stakes and lanterns to guide vessels through the narrow channel of San Diego's mud flats.