The Upper Arkansas, which drops almost a vertical mile in its 150-mile navigable stretch, offers rapids of all classes.

The summit loomed more than a vertical mile above, though clouds obscured its upper reaches in a murky stew.

"The tunnel becomes nearly vertical a few miles farther along," Saa said.

He looked down-it was a long drop, still most of a vertical mile of drop-and then stepped backward off the edge.

Its upper reaches are almost three vertical miles (4.8 km) below the summit of Mount McKinley.

At the bottom, roughly a vertical mile below the rim, flowed the sinuous Colorado River.

The summit, however, was still a vertical mile above, 'wreathed in a nimbus of gale-borne condensation.

Located in the northeastern part of the park, Mount Merritt rises dramatically a vertical mile above nearby rivers.

You are now a vertical mile below the rim and the rocks have been dated to the immense age of 2000 million years.

The cave's deepest known point is nearly one vertical mile and seven horizontal miles from the entrance, ending in a terminal sump.