Just a few miles outside the United States, six American men live a world away.
Crowded into a damp and stuffy 10-by-18-foot windowless cell, the men pass around well-read copies of U.S. newspapers and wait for the weekly aid package that helps them survive in the Tijuana prison known as "El Pueblito," or the Little Village.
Home to more U.S. citizens than any other foreign penitentiary, it is a facility full of contradictions: convicted drug dealers with easy access to drugs; locked-in inmates who add locks to their cells each night for security; and prisoners who might prefer custody to freedom.
"Probably 50% of the people, they love it here," says inmate David Nunoz of Los Angeles. "You could open the gates tomorrow and they wouldn't leave."
Last month 61 Americans lived among the 5,000 inmates at El Pueblito, a nickname based on its bustling, urban community feel.
Restaurants and juice stands line concrete alleys. There's a small Roman Catholic church and a windowless garment factory, where prisoners sit at sewing machines.
At a booth, inmates line up to pass money through a small slot and receive heroin, cocaine and marijuana from anonymous suppliers.
In a shantytown off the main yard, the families of dozens of Mexican inmates, including some with small children, have set up permanent residence.
"It's like living in a bad neighborhood," Nunoz said.
It is easy to disappear within the high walls of the noisy and chaotic La Mesa State Penitentiary. A 26-year-old Tijuana woman accused of murdering her husband vanished last week.
"We can't say for sure whether she escaped," Warden Jesus Torres Espejo told the Tijuana newspaper Frontera. "We're searching inside, but there are many corners where an inmate could hide."
Nunoz, a heavily tattooed 40-year-old, knows El Pueblito well. He's in the final months of a seven-year sentence for heroin possession.
His status as a long-term resident enables him to walk through the narrow alleyways and corridors without being harassed. Inmates and guards, who have a minimal presence inside the prison, greet him by his nickname, "Scooby."
Other Americans, like 47-year-old David Brisendine of San Diego, face a gauntlet of outstretched palms and demands for money.
"Hey, gimme some money, white boy," one man says in English to Brisendine, a lanky man who towers over many inmates as he works his way through the crowded, gritty prison yard.
But Brisendine, who is halfway through a nearly three-year sentence for methamphetamine possession, keeps his eyes to the ground.
"I don't even really notice it anymore. Besides, I don't have any money left anyway," he said.
It is a common lament at La Mesa, where everything from a bunk to decent food has a price and anything, including a private room with cable television, is available for inmates with the means to pay for it.
A onetime $50 payment to guards buys space in a cell, as opposed to a hallway. Seeing a visitor costs 15 pesos, or about $1.50. Newcomers must pay $10 to get out of the daily work detail. Drinking water is 12 pesos, or about $1.20, for five gallons.
It may not sound like much, but it's everything to prisoners with no income.
"You don't get anything for free here," said one Guatemalan inmate, who asked that his name not be used. "You're lucky if they give you a blanket."
Many Mexican inmates get supplies from family and friends in Tijuana. The Americans, however, depend on help from David Walden, a San Diego minister who has brought in supplies for five years, and Sister Antonia Brenner, a Catholic nun who has been helping prisoners at La Mesa for more than two decades.
Each week, Walden and other volunteers bring boxes of food, clothing and mail for the inmates. Nunoz escorts the visitors through the yard to make sure the supplies reach the Americans.
"The first time I came, I felt like I was walking onto the set of a movie," said Walden, 51. "It was all just so unreal."
He prays with the inmates, tries to help them with their legal problems and, for many, serves as their main contact with the outside world.
Their experience isn't entirely foreign to Walden: A former financial advisor and movie producer from Orange County, he was convicted of securities fraud in 1984 and sentenced to 16 months in prison. Although the conviction was reversed, he served seven months.
"When you go to prison, everybody bails on you," said Walden, who often speaks of his experience in his sermons. "That's why I can relate to these guys."
Walden's weekly arrival at the cell shared by Nunoz, Brisendine and four other Americans is the major event of the week. Inmates crowd into the room, which has the acrid odor of tight quarters shared by men without regular access to showers, as he passes out their mail and envelopes with small amounts of cash.
The men have a small television and share newspapers sent to another, relatively wealthy American inmate in the prison. They hang sheets from the ceiling to enclose each bunk and provide some privacy. After the guards lock their cell gate at 10 p.m., they add a heavy padlock on a thick chain.
While some inmates may be comfortable in El Pueblito, the American cellmates are eager to go home.
"Before I got arrested, I never really did like Mexico all that much," Brisendine said. "But I can tell you that when I get out of here, I'm never coming back."