Land here is limited in all directions: by the Mexican border to the south, the ocean to the west, the Marine base at Camp Pendleton to the north, and the Cleveland National Forest east of the city.

• 圣迭戈的四面都有屏障，难以延展：南面是墨西哥边境，西面是太平洋，北面是潘德尔顿海军基地，东面是克里夫兰国家森林公园。