The Kaluts is a large area in which the rough, rocky Lut Desert has been sculpted by millennia of wind erosion into long lines of photogenic formations. Much the most impressive of these are five- to 10-storey high yardangs (‘sand castles’) with vertical or stepped sides. They are especially spectacular at dawn and sunset when light and shadows turn the scene into a shimmering canvas of gold and brown.
The term 'Kaluts' actually applies more accurately as the general term for a series of different erosion patterns – the most dramatic are fortress-like vertical towers and stepped mesas, like earthen versions of what you might see in Monument Valley (USA). The most spectacular are near a parking area signed 'Kalout'. Further east are tokhmemorghi (egg-shaped muddy hillocks) and essentially similar merikhi (rounded on one side but sharply cut into verticals on the other).
Amid all the mirages, water really does flow through the desert: at Rud Shur bridge you'll cross a real, if tiny, meandering stream. Another 30km east, the erosion pattern becomes a series of vertically serrated cliffs.