People exit a plane from Ireland that made an emergency landing because of an unspecified threat. ((AP Photo/Matt Rourke)) PHILADELPHIA -- A bomb threat investigation that prompted a search of a trans-Atlantic flight and questioning of its passengers has turned up nothing suspicious, officials said. US Airways Flight 777 from Shannon, Ireland, landed in an isolated part of Philadelphia International Airport on Wednesday afternoon and was met on the tarmac by fire trucks and federal and local authorities. A telephone...

The sinkhole in a Kansas field estimated to be 90 feet deep and 200-300 feet wide. (Wallace County Sheriff's Department) SHARON SPRINGS, Kan. — A sinkhole estimated to be about 90 feet deep in western Kansas is drawing so many onlookers that the landowner is pleading for people to stay away. The sinkhole, which is 200 to 300 feet wide, was discovered July 31 in a pasture several miles north of Sharon Springs on land owned by 82-year-old Margaret Hoss...

In an effort to increase tourism to remote Daocheng County inGarzê Tibetan Autonomous Prefecture of Sichuan Province, China, an area known for its sacred mountain peaks and alpine valleys, the Chinese government is currently building the Daocheng Yading Airport, which at 14,469 feet (4,410 m) above sea level, will become the world's highest tourism airport. The airport, likely to cost around $238million, is expected to open later this year and will offer routes through to the western cities of Chengdu,...

In this Monday, July 29, 2013 photo, the Terrafugia roadable plane flies during the Experimental Aircraft Association's AirVenture in Oshkosh, Wis. (AP Photo/The Oshkosh Northwestern, Joe Sienkiewicz) Can't decide if you'd rather hop in the car or take to the skies for your next big trip? You might not have to choose anymore. The Transition flying car, which had a test flight in March of this year, was recently on display at an air show in Oshkosh, Wis. for its...

Tourists ride past the Desert Lotus Hotel under construction in Xiangshawan Desert, also called Sounding Sand Desert on July 17, 2013, in Ordos of Inner Mongolia Autonomous Region, China. (Feng Li/Getty Images) Xiangshawan Desert in the Inner Mongolia region of China probably isn't the first place you'd look at for a vacation. In the wintertime, temperatures are frigid with frequent blizzards, and the summertime brings hot, dry weather that can cause huge sandstorms. Yet those conditions are exactly what make...

Hersheypark is a 110-acre theme park built in 1907 that features more than 65 rides and attractions, including 11 roller coasters, more than 20 kiddie rides, live daily entertainment, games, food and shops. (Hershey Entertainment & Resorts Company) Thanks to its founder, the town of Hershey, PA is known as The Sweetest Place on Earth. A chocolate lover's dream destination, Hershey features a wide array of attractions and events that are designed to please every age group. Milton Snavely Hershey...

A picture taken on August 4, 2013 shows the Vexin region countryside pictured from an Airship Paris zeppelin. Absent from the skies of the French Capital for nearly a century, the airship now reawakens the past to offer its passengers a flight over Paris. (ERIC FEFERBERG/AFP/Getty Images) It's a view of Paris from the air that hasn't been offered in more than 30 years. Almost 1,000 feet up into the sky, traveling at a leisurely speed of 90 kph (55...

Its climate can be oppressively hot and arid, and its terrain rugged and forbidding, but the Negev Desert in southern Israel is undergoing a transformation -- from desolate land to a thriving tourist destination. In fact, travel guide publisher Lonely Planet ranked itsecond in its list of Top 10 regional travel destinations for 2013. Framed by the borders of Jordan and Egypt, with its southernmost tip at Eilat, Negev Desert may be far from civilization, but it is also rich...

Yunyan Pagoda, China Many consider the Leaning Tower of Pisa one of the world's architectural wonders, but it's not the only famously tilting structure in the world. Around the globe, there are other stunning slanted spires and tottering towers. Many of these famous inclines were Mother Nature's doing -- a result of an earthquake or a nearby sinkhole -- and while officials have taken measures to stabilize some of their leaning monuments, all of them are still vulnerable to weather's...

This unusual cityscape of New York's Time Square was taken by photographer Stephen Wilkes, who spent up to 15 hours and shot close to 1,500 photos to create just one composite image. (Stephen Wilkes/Caters News Agency) “Weather is critical, especially wind,” photographer Stephen Wilkes explained to Weather.com about capturing photos for his “Day to Night” series, which feature dramatic cityscapes shot from high-vantage points. “When I photograph from a lift truck 50 to 100 feet in the air, any wind...

Beach sand dune on Emerald Coast, Florida. (Thinkstock) Florida's beaches attract tourists from around the country, but they might not be able to support big crowds for much longer, because the beaches are running out of sand. According to the Associated Press, the U.S. Army Corps of Engineers has prioritized the sand loss problem in Miami-Dade county, where some of the most popular beaches are located, and are holding public meetings to discuss where new sources of sand might be...

Lake Guatavita - Colombia Everyone has heard of treasure buried at the bottom of the ocean after violent storms caused shipwrecks -- an estimated three million wrecks are scattered across the bottom of the seas, and they could be valued as high as $60 billion, says Popular Mechanics. But shipwrecks are hardly the only places where treasures have been lost. From a lake in Colombia that's thought to be the site of El Dorado to a Canadian island that might...

A view of the New World on the ostrich egg globe. (Used with permission of The Portolan, copyright Washington Map Society) A map etched into the surface of a grapefruit-sized ostrich egg from the early 1500s might be the oldest known globe to show the New World, according to experts. The globe, which was purchased by an anonymous collector at the London map fair in 2012, might have been the model for what was until now thought to be the...