The Tijuana Estuary Visitor Center (part of the Tijuana River National Estuarine Research Reserve) is located at 3rd Street and Caspian Way in Imperial Beach, the most southwestern city in the United States. The Tijuana Estuary is one of the few salt marshes remaining in Southern California. The site is an essential breeding, feeding and nesting ground and key stopover point on the Pacific Flyway for over 370 species of migratory and native birds, including six endangered species.
The Reserve offers four miles of walking trails, taking visitors into prime bird watching areas and down to the river mouth where the Tijuana River meets the Pacific Ocean. Visitors may explore the park on their own or join one of the free guided nature and bird walks on weekends.
Border Field State Park is located in the southwestern corner of the Reserve, on a bluff overlooking the ocean, the estuary, and the bullring that lies just south of the U.S./Mexico border. A marker on the bluff, first placed there in 1851 just after the treaty of Guadalupe Hidalgo, delineates the western beginning of the International Border.
The Tijuana Estuary was designated as "A Wetland of International Importance" by the International Ramsar Convention in 2005.
