The drug runners breach every United States frontier, but one of their main targets is San Ysidro, Calif., America's busiest border crossing, the fragile demarcation line that separates San Diego from the smuggler's paradise of Tijuana.
When the taxi deposited us at the border crossing, the pedestrian line stretched out of sight.
It has left Abkhazia's economy highly dependent on Russia, which maintains a border crossing and railway line to Sukhumi.
Rebels have made the most headway right along the Turkish frontier, which has allowed them to secure the crucial border crossing and supply line.
One of ISIS's most striking videos shows jihadis destroying the border crossing between Iraq and Syria, a line established by the infamous Sykes-Picot agreement, in 1916.
After months of an exodus, driven by the fighting in the mountains, refugees returning home jam the border crossing in a long line.
Because Flanagan South is not a border-crossing line, it doesn't require the State Department or Obama's approval.
At Busia, a major border crossing with Kenya, trucks are lined up for hours, or even days, awaiting inspection.
Some of the best material on "Kingpin" lies in the mundane workings of the drug trade, from illegal border crossing to the shabby, assembly-line cocaine labs.
Since 1998, Agua Prieta, a gritty desert town that shares the border with Douglas, has been the busiest border crossing area along the 2,000-mile 2,000-mileine between Mexico andividingited States.
If a migrant can pay enough, heading north can be as simple as waiting in line at a border crossing, handing a forged identity document to a border guard and, if it works, strolling into the United States.
