In many places longitudinal dunes are found exceeding a day's journey in length, the valleys between which take three or four hours to cross; but the most striking feature of the Nafud are the high crescent-shaped sand-hills, known locally as falk or falj, described by Blunt and Huber, who devoted some time to their investigation.
The latter is fringed throughout its whole length by a chain of dunes, which rise in places to a height of nearly 200 ft.
When the ache had left her legs numb, and her breath was no longer coming in gasps, they started out again - across sand dunes - up and down.
Of Limassol, among sandy hills and sand-dunes, which perhaps explain its name in Greek (ti t aOos, sand).
The coast-line extends in a double curve from south-west to northeast, and is formed by a row of sand dunes, 171 m.