Story highlights

Teen arrested for sending out al Qaeda-like tweet threat to American Airlines

Other ill-advised traveler behaviors including defacing ancient monuments

The TSA seized nearly 2,000 guns last year during security screenings

CNN  — 

Threatening an airline on Twitter is a terrible idea.

An airline such as American Airlines – which was attacked by terrorists on September 11, 2001, and lost two planes filled with passengers and crew – is likely to take your public threats seriously.

It might even get you arrested, as was the case of the 14-year-old Dutch girl who recently wrote, “@AmericanAir hello my name’s Ibrahim and I’m from Afghanistan. I’m part of Al Qaida and on June 1st I’m gonna do something really big bye.” (The teen was arrested Monday afternoon.)

Teen arrested for tweeting airline terror threat

Foolishness – at home or abroad – rarely yields great results. So please stop doing stupid stuff while traveling. Just stop it.

You’re making the rest of us polite, culture-seeking, nature-loving and happy-to-practice-our-Spanish (or French or Arabic) tourists look bad. And you could end up in jail. Here are a few stupid examples of things you shouldn’t do:

Don’t knock over ancient rocks. Never mind that the Boy Scout leaders who knocked over rocks dating back millions of years in Utah’s Goblin Valley State Park should have known better. Our nation’s national and state parks are not anyone’s private playground.

Please respect them and leave the ancient wonders intact for everyone to enjoy. (In March, Utah resident Glenn Taylor pleaded guilty to criminal mischief and another Utah man, David Hall, pleaded guilty to attempted criminal mischief. Both men received a year of probation and fines.)

Don’t parade around naked in inappropriate places. Peruvian officials are getting annoyed by naked tourists converging on Machu Picchu.

“There are places in the world that people can get naked, but not all places are (appropriate) for getting undressed,” Alfredo Mormontoy Atayupanqui, director of archaeological resources for Peru’s Ministry of Culture, told CNN.

Perhaps a 15th century Inca treasure and World Heritage Site isn’t one of those places. Park rules printed on the back of your admission ticket warn against being nude in public, Mormontoy says. Security around the site is being increased, and we have the naked visitors to thank for it.

Please don’t disrobe, unless it’s allowed by local custom! (See Nice, France, for topless beaches.)

Don’t write on sacred monuments. Not all of the badly behaving travelers are Americans. Last year, a 15-year-old Chinese tourist defaced a stone sculpture in the 3,500-year-old Luxor Temple with graffiti. The teen carved “Ding Jinhao was here” in Chinese on a sculpture. The graffiti was photographed by another Chinese tourist and posted online.

When his graffiti went viral, and he was tracked down, his parents apologized in a China Daily report, promising they were taking responsibility for what their son had done.

Don’t climb them either. Visitors to the pyramids at Giza, Egypt, aren’t supposed to climb them. Russian photographer Vadim Makhorov and a group of his friends, in search of glorious photos, apparently didn’t think the rules applied to them.

While Makhorov apologized for climbing the pyramids,he’s made a habit of climbing tall structures. He’s since scaled the world’s second-tallest building, the unfinished Shanghai Tower in China.

Don’t pack guns in your carry on. If you’ve got one, remember to ask yourself: “Where’s my gun?” Some people actually forget where their guns are located until the Transportation Security Administration finds them. The TSA confiscated 1,813 guns at the airport last year, and Hartsfield-Jackson Atlanta International Airport came in first place with 111 guns seized.

If you meant to have your gun in your carry-on bag, know there are legal ways to transport weapons – but not the way you did it. Many hunters do it properly all the time, and TSA and U.S. Customs officials know how to clear your weapons safely.

Have you ever witnessed fellow travelers making really horrendous mistakes while traveling? Please share your thoughts in the comments section below.