A provocative new hypothesis suggests that Yosemite Valley was carved by an ancient volcano and a disappearing river, both of which have long since eroded away. Geologists have long debated why ...

This week's science news has taken us in a time machine, from the discovery of a 506 million-year-old fossil of a bizarre "sea monster" that breathed through its butt to the death of the universe ...

Add Yahoo as a preferred source to see more of our stories on Google. In about the time it takes to drive from San Francisco to Yosemite Valley or Lake Tahoe, you could be starting a hike to the top ...

Yosemite National Park is one of the most visited sites in the country, but this underrated California alternative is just as ...