It's not pretty, but this hole in the ground is the sign of an expert drug smuggler. It's part of a 600-yard tunnel under the California-Mexico border and it connects a warehouse in Tijuana with one in San Diego.
Now while some might think that a smuggling tunnel like this is little more than a plot device in Weeds, it seems it's not terribly uncommon—in fact, about 125 have been discovered since the 1990s. The only trouble is that it's quite tough to actually find them. There are special U.S. border tunnel task forces dedicated to tracking them down and they use the latest ground-penetrating technology as well as robot scouts to search for and through them.
Despite all that tech, there aren't too many details available to us about the recently discovered tunnel in the photo above. We do know that it definitely housed a reasonably high-tech operation considering that it contained proper rail, lighting and ventilation systems as well as 30 tons of marijuana. [CNN]