The Grand Canyon is more than just a big, gaping stretch. It's a prime spot for river adventures that can last from a day to ...

Most people think the bottom of the ocean is like a giant bathtub filled ... canyons far grander than the Grand Canyon and towering vertical cliffs rising up three miles—more than twice the ...

First, that the Grand Canyon ... side of the canyon. Yeah. I see, yeah, right here. DR DAVE THAYER: This red layer right here would be a silt stone that formed at the edge of an ocean.