In some places, there are steep rock walls hundreds of feet high.
Where the Arctic Red River enters from the south, the Mackenzie again flows between steep rock walls, which rise up to 200 feet (60 metres) directly from the water.
At 105 metres high, with the river flowing below and steep rock walls on either side, it feels a little daring, but not terrifying.
What we were looking at was a galaxy full of glow-worms, clinging to the steep rock walls on either side, each one a bright star.
Al-Nafūd fills an irregular basin surrounded by hills, ridges, and buttes (isolated flat-topped hills rising abruptly from the surrounding land) or mesas (table-topped plateaus of relatively small extent with steep rock walls).
The road — Highway 1, far north here of the famous Big Sur stretch better known to tourists — weaves through a dense eucalyptus grove, ascends a steep incline, passes through a jagged gap between two steep rock walls, and emerges as a ribbon of clifftop roadway known locally as Devil's Slide.
But there are little chips where the white gypsum shows through, and if you look up in the dim light it's easy to imagine yourself in a deep canyon, with steep rock walls on either side framing a cold, starry night above.
Landslide dams commonly occur in narrow valleys (Fan et al., 2012c), bounded by steep sheer rock walls and by uneven mountains where the mass in motion does not have space to disperse itself.
Waterfalls poured down from the steep jungle off sheer rock walls.
Above were the steep stone walls of the local cemetery.
