San Diego has something super-useful city guide to you and the Old Tows being one among them.
Old Town
You might be interested to know that in 1889, a horse-drawn streetcar line was built through El Campo Santo Cemetery, where more than 20 men, women, and children were interred under what is now San Diego Ave. If you look down on the sidewalk/road just outside the cemetery gates, you’ll be able to see small brass circles marking the grave sites that were found in 1993 via ground-penetrating radar.