The curved roof, stained by ages of leakage, with buff and black and rust-colored streaks, swept up and loomed higher and seemed to soar to the rim of the cliff.

Here again was a magnificent arch, such as formed the grand gateway to the valley, only in this instance it formed the dome of a cave instead of the span of a bridge.
Venters passed onward and upward.

The stones he dislodged rolled down with strange, hollow crack and roar.

He had climbed a hundred rods inward, and yet he had not reached the base of the shelf where the cliff-dwellings rested, a long half-circle of connected stone house, with little dark holes that he had fancied were eyes.

At length he gained the base of the shelf, and here found steps cut in the rock.
These facilitated climbing, and as he went up he thought how easily this vanished race of men might once have held that stronghold against an army.