Sections of the 1,900 mile U.S.-Mexico border can be a tense place for both citizens and U.S. and Mexico customs and border patrol officials, but both sides are working closely together -- and it has nothing to do with border control, but aviation.

According to The New York Times, "in San Diego, private investors on both sides of the border are taking a different tack, building a bridge to Tijuana International Airport with the expectation of turning it into a low-cost alternative to San Diego's boxed-in, one-runway airport."

Slated for next year -- "if all goes according to plan, air travelers in this region will be able to park their cars in the United States and walk across an enclosed 325-foot passageway directly to Tijuana International."

This unique project that would make Tijuana International "a rare airport" in that it that would let passengers land in one country and leave in another. There's two airports on the Swiss-French border that pull this off and a shuttle runs passengers with connecting flights between airports in Hong Kong and Shenzhen, across the border in mainland China.

The effort is spearheaded by Chicago real estate magnate Sam Zell, who "promises to help fulfill an early dream of the 20-year-old North American Free Trade Agreement: problem-free travel between Mexico and the United States."

Each year, 2.4 million travelers from the United States use the Tijuana airport, even if it means waiting for hours at the border. They provide the airport with nearly 60 percent of its traffic, according to the New York Times.

Why would this be enticing for flyers? Cost of course!

"It is worth the trouble for those people because fares in Tijuana are substantially lower -- up to 50 percent less to fly throughout Mexico -- than at San Diego's Lindbergh Field or other airports, like Los Angeles International."