Located within the Tijuana River National Estuarine Research Reserve, Border Field State Park sits in the very southwestern corner of the United States, 15 miles south of San Diego. This important wildlife habitat, comprised of sand dunes and salt marshes, gives refuge to critically threatened and endangered birds such as the Western Snowy Plover, the California Least Tern, and the Light-footed Ridgway's Rail.

The park provides restrooms, picnic areas, barbecues, horse corrals, interpretive displays, and scenic views across the beach and estuary. Visitors enjoy hiking, horseback riding, photography, and bird watching along the 1.5 mile stretch of beach and inland trails. The Park does not recommend swimming or wading, due to hazardous conditions, such as inshore holes, rip currents, and the lack of lifeguard service within the Park.

Border Monument number 258 can be viewed from Monument Mesa, however there is no close access because it is now behind two border fences. You can still see the bunkers which were leftover from World War II. Read more about the history of this area.