TIJUANA, Mexico - It looks like any Southern California traffic jam - except you can buy a cappuccino and a 4-foot statue of Jesus from your car while watching dogs sniff vehicles for drugs.
This is the U.S.-Mexico border's most congested crossing, where local residents say already epic lines into San Diego have grown even longer since January, when the U.S. began phasing out a long-standing practice of allowing people they believed to be American citizens to enter by simply stating their citizenship.
Border guards now require most crossers to present a U.S. passport or other proof of citizenship, such as a birth certificate - though they are still permitted to exercise their own judgment in order to keep lines moving. As always, Mexican citizens and other foreign nationals must show valid immigration documents to enter.
Still longer waits may be coming for people trying to get to jobs, homes, in-laws and weekend hangouts are scattered across both halves of the border's largest metropolis.
As of next June, all U.S. citizens will have to present a passport or security-enhanced card, much like an electronic toll tag, to cross - or risk being waved out of line for a rigorous security check.
More than half the 21 million cars crossing from Tijuana each year wait 90 minutes or more, with a fourth stuck for more than two hours, according to survey data collected before the January rule change and published this month by Tijuana's College of the Northern Frontier.
At the crossing from Ciudad Juarez to El Paso, Texas, the second most congested border point, only 13 percent of the 16 million cars going north each year wait longer than two hours, it said.
The border crossing at Laredo, Texas, draws more commercial truck traffic. But larger and wealthier San Diego has one of the world's largest cross-border flows of people, with more than 130,000 heading north each day through the San Ysidro crossing and nearby Otay Mesa, opened in 1985.
Local officials estimate the long waits cost businesses in Tijuana and San Diego a combined $7.2 billion last year, in losses due to delayed freight, discouraged shoppers and work hours spent in line.
Still, the bottleneck has proved alluring for vendors, and the Mexican side of the crossing bustles with commerce - legal and otherwise.
"The saddle is real leather!" said street vendor Elias Segoviano, 29, waving a toy horse at a reluctant buyer queued up at the San Ysidro crossing. His pitch continued right up to the yellow stripe on the pavement marking U.S. territory.
Just over the boundary, Customs and Border Patrol dogs working the same lane earlier that day found some 90 pounds of marijuana packed inside the tires of a Chevrolet van, part of the daily battle to keep illegal people and drugs out of the U.S.
Regular crossers hardly blink at the show. Vicky Hernandez, 23, plucked her eyebrows on the way to work at a San Diego accounting firm. Marine repairman Luis Mendoza, text-messaging his wife as he sat behind the wheel, said he sometimes sleeps overnight in his clients' boats to skip the border wait.
Both Hernandez and Mendoza are U.S. citizens. But like many among the San Diego-Tijuana area's 5 million residents, they put up with the wait so they can keep their U.S. jobs while staying close to family and avoiding California's high rents.
"My dad's retired already, so he can't afford rent over there anymore," said Hernandez, who grew up north of the border in Imperial Beach. "I was planning on moving back by myself, but I was looking at apartments for like $1,000 a month, and that's $1,000 a month I can save."
Before the Sept. 11 attack on the U.S., border waits sometimes reached an hour at San Ysidro. Today's considerably longer lines will likely get worse before they get better.
Planing for a $577 million U.S. expansion of the San Ysidro port of entry is under way, with the current 24 lanes to get an additional six by 2014 along with a double-stack checkpoint system - think checkout lanes at Target. However, Tijuana has yet to come up with the money to build matching lanes on its side of the border.
San Diego-area governments also want to build a third border crossing east of the Otay Mesa port - that would be paid for by a toll, to avoid the long wait for U.S. federal money. But the project is still only a proposal. Tijuana would have to bulldoze a squatters' neighborhood along the fence to clear the proposed path.
For now, the border's outdated infrastructure - the San Ysidro port has not grown since it opened in 1974 - can only groan under the traffic.
"Once we open all these lanes, that's it. We're not going go any faster processing vehicles. We're not going to allow terrorists to come into this country because of the pressure of the wait time," the San Ysidro Port director, Oscar Preciado, said, talking over the rumble of thousands of idling cars and trucks.
Officers at San Ysidro and Otay Mesa now seize more than 40 percent of the marijuana, cocaine and heroin and nearly 80 percent of the methamphetamine captured at U.S.-Mexico border crossings.
They also catch an average of more than 100 illegal immigrants each day - some so desperate to cross they now hide under car hoods, squeezed in with the engine block.
Border officials say they expect to see even more illegal immigrants and drug cargos at the official crossings because the U.S. border fence is being expanded and fortified in areas now commonly used for smuggling.
Dr. Gustavo del Castillo, author of the wait times study, said the delays are a far cry from the "seamless border" once trumpeted by the 1994 North American Free Trade Agreement.
"Now you have a border that's beginning to look like East and West Germany, with razor wire and multiple gates. Mexicans are sort of at a loss, wondering