Khor Al Adaid is an arm of the Arabian Gulf that pushes about ten kilometres inland into a moving sand desert. Seawater winds down a narrow channel into a lagoon almost closed off by barchan dunes forty to sixty metres tall. No road runs to the shore. You arrive by four-wheel drive with the tyres let down, and the last minutes are the ones that stay with you. The vehicle tips over a dune crest, slides down the face, and the sand simply stops at warm, shallow, clear water. Wade in and it dries to a white salt film on your skin. With no river feeding it and only that one thin channel back to the Gulf, evaporation has made the lagoon about half again as salty as the open ocean.
The silence is the other surprise: no traffic, no boats, only the tide working against a wall of sand. Few animals tolerate water this salty, though dugongs and turtles use the outer bay and ospreys nest on its islets. The bay itself is young. Rising seas drowned an old river valley here over roughly the last 6,000 years, and the dunes above it are still travelling south across Qatar. After dark this is one of the few corners of the country, among the most light-polluted on Earth, where the Milky Way is plainly visible. Qatar declared the area a nature reserve in 2007 — its largest, some 1,833 square kilometres — and placed it on UNESCO's Tentative List. Almost everyone comes on a licensed safari from Doha, and the camps run through the cool season, roughly mid-October to mid-April. The border with Saudi Arabia crosses the far side of the khor, so carry your passport.