A small fence separates densely populated Tijuana, Mexico, right, from the United States in the Border Patrol's San Diego Sector. Construction is underway to extend a secondary fence over the top of this hill and eventually to the Pacific Ocean.
El Paso (foreground) and Juarez (background) are on the front line of a border war between law enforcement and Mexican cartels.
Nogales, Arizona - Nogales, Sonora
Members of the Mexican Federal Police guard over 105 tonnes of marijuana in the border town of Tijuana, Mexico. Mexico's largest ever haul of packaged marijuana could be even more than an estimated 105 tonnes and was likely taken from the Sinaloa drug gang - Oct 2010.
Rio Grand River Gorge
Rio Grande River, international border, Texas
A recently constructed section of the controversial US-Mexico border fence expansion project crosses previously pristine desert sands at sunrise on March 14, 2009 between Yuma, Arizona and Calexico, California. A top Homeland Security official told a House panel that the department could ultimately respond to escalating violence of warring Mexican drug cartels by deploying military personnel and equipment to the region. 6,290 people were killed in the violence in Mexico in 2008, according to Mexican officials, and more than 1,000 in the first eight weeks of this year. Hundreds of kidnappings in Phoenix during the same time period were blamed on the drug trade. The new barrier between the US and Mexico stands 15 feet tall and sits on top of the sand so it can lifted by a machine and repositioned whenever the migrating desert dunes begin to bury it. The almost seven miles of floating fence cost about $6 million per mile to build.
