Socotra lies in the Indian Ocean off the coast of Yemen and is one of the most biologically distinctive places on earth. A third of its plant life grows nowhere else.
Its best-known species is the dragon blood tree, whose umbrella-shaped crown appears across the island's highland plateaus, alongside bottle trees, limestone caves, white dunes and turquoise bays.
The archipelago is a UNESCO World Heritage Site, recognised for an isolation that produced an ecology found nowhere else in the Arab world.