For college students, March Madness usually means basketball and Spring Break. But on South Padre Island in Texas, March Madness is taking on a whole new meaning.

Students there say the real madness would be to take the traditional 30-minute trip to the Mexican border for the popular "Two-Nation Vacation."

News of gun battles between Mexican soldiers and drug cartels in border cities are keeping tourists away and prompting many parents to dole out a stern warning: "Don't go to Mexico."

Bryanna Lindblom is visiting for a few days from University of Central Missouri, and she says she wouldn't think of going to Mexico. "I think my mom would freak out," she says. "She'd probably have a little bit of a cow."

It's easy to see why parents are concerned.

In Ciudad Juarez, just across the border from El Paso, machine-gun-toting Mexican soldiers have been deployed to the border in armored personnel carriers to quell drug cartel violence. The situation is the same in other Mexican border towns. But the sight of armed men patrolling the streets makes many visitors nervous.

As a result, local businesses that depend on tourist traffic to Mexico say they are really hurting this year.

Debra Fassold's family has been running the Original Tours company since the 1970s. Fassold says she used to have 10 to 20 trips from South Padre Island to Matamoros, Mexico, each day. But now she says she doesn't have enough customers for even one tour.

One visit to the border crossing in nearby Brownsville confirms that Spring Breakers are staying in South Padre. A border guard said he'd seen only two kids go across the entire day.

The U.S. State Department is warning American visitors to Matamoros and Nuevo Progresso to "be especially aware of safety and security concerns due to increased violence in recent years between rival drug trafficking gangs," although they say that it's "unlikely that American visitors would get caught up in the violence."

Fassold goes further and notes that you're just as likely to be a victim of violence in any American city. "If you go on a tour and you see, it's safe over there," she said.

Many college kids in South Padre said that with all the parties, girls and deejays spinning on every block on the American side of the border, there was no reason to risk a trip to Mexico.

Said Evan Bookstaff, a University of Texas student: "Is it really worth the extra 30 miles when you can have fun here?"

FOX News correspondent Kris Gutierrez and The Associated Press contributed to this report.