Chelsea, Massachusetts, is plagued by what is known as the Urban Heat Island effect, in which pavement and vehicles soak up ...

The Sahara wasn’t always a desert—14,000 years ago, it was alive with rivers, people, and wildlife. Now, new evidence is uncovering a lost chapter of human history.

Read our expert reviews of Las Vegas hotels. Browse and book the best accommodation in Las Vegas, based on location, style, facilities, rooms and dining.