In 1848 , the U.S. built a pyramidal statue on the San Diego beach to mark the end of the Mexican-American War and the initial boundary point between Mexico and U.S. On August 18 , 1971 , Friendship Park was inaugurated by then-First Lady Pat Nixon as a symbol of binational friendship , when it was declared a national monument . Until 1994 , there was only a simple barbed wire fence , and anyone can meet on the border under the supervision of the U.S. Border Patrol . Various social events have taken place in this park , including yoga classes , religious services , weddings , dancing , and baptisms . In 1994 amidst widespread hysteria about unauthorized immigration between San Diego and Tijuana , a 14-mile long fence was constructed on the border between San Diego and Tijuana as part of Operation Gatekeeper , including one in Friendship Park . Border security was tightened in the 1990s and again after the September 11 terrorism attacks in 2001 . During that time , people on opposite sides of the border were still able to touch and pass objects through the barrier . In 2009 , the U.S. Department of Homeland Security closed down Friendship Park and a second parallel fence was created which stretches into the Pacific Ocean that includes barbed wires , sensors , and surveillance cameras . A 20-foot wide border patrol access road was also created , along with a third 20-foot wall of steel bars
September 11 terrorism attacks
September 11 attacks
Friendship Park (San Diego–Tijuana)