The Dahlak Archipelago is more than 120 low coral islands in the Red Sea off Massawa, in Eritrea, only three of them settled, with medieval gravestones, rain cisterns and vast colonies of seabirds, and reefs that see almost no divers, so that the coral is unbroken and the turtles unbothered, reached by wooden boat from Massawa with a permit and a guide. The islands were a sultanate and a pearl fishery from Roman times, dangerous breath-hold work much of it once forced on enslaved divers, and the old town on Dahlak Kebir, the largest island, keeps the basalt tombstones of the sultans cut in angular Kufic script and the rain cisterns hewn into the coral rock that let people live on islands with no springs; the wooden boats thread between dozens of islets, each ringed by its own pale sandbar and turquoise shallows, and the snorkelling is straight off the sand over reef that has never been broken, with hawksbill turtles hauling out on the sand of Mojeidi to nest in late May and dugongs in the seagrass. On the island of Nokra the rusting hulls of a Cold War Soviet naval base lie half-sunk where they were left in 1991, a secret station where submarines were repaired far from home waters, dived among the coral that has taken them.
The birds fill the islands through the hottest months, crab plovers digging their nesting burrows in early May, the white-eyed gulls of the Red Sea laying from June and the tern islands loud with chicks into August, so that in summer the low sand of Mojeidi vanishes under nesting terns and the noise reaches the boat across the water long before the island does. The heat on the water passes forty degrees in summer, and the Eritrean government admits few visitors, so the archipelago is one of the emptiest reefs in the world, fished by the islanders in dhows. Dahlak is a scatter of coral islands that time forgot, and the turtles and the terns have them.