It's not just Niagara Falls. Many states in the US have impressive waterfalls. Some require a hike, but others are easy to ...

In stark black-and-white and stunning color, this year's winning photographs capture global events on a human scale ...

The Colorado River system is the lifeblood of the southwest, delivering water to 40 million people across the United States ...

At the uppermost reaches of stream networks, headwaters dry up during the summer, then burst back into existence when spring ...