The journey home involves waiting times – sometimes just a few minutes, sometimes half an hour. Jodi Cilley usually puts on her make-up when it takes a little longer, writes e-mails or calls her family while the line of cars moves faster, sometimes slower along one of the best-secured borders in the world.

Cilley, an American, has crossed the San Ysidro border crossing, which connects Tijuana, Mexico, with the suburbs of San Diego, California, hundreds of times. “I’ve seen everything here,” says the 45-year-old. “People selling life-size statues of Jesus, drug busts, cars just bursting into flames.”