Vincent Grafhorst / Minden / River in sandstone cave, Sof Omar Cave, Ethiopia

Vincent Grafhorst / Minden / Crater of active volcano at twilight, Erta Ale, Danakil Depression, Ethiopia

Vincent Grafhorst / Stream in Harenna Forest, Bale Mountains National Park, Ethiopia

Vincent Grafhorst / Tree with epiphytes, Harenna Forest, Bale Mountains National Park, Ethiopia

Vincent Grafhorst / Salt flat, Lake Asale, Danakil Depression, Ethiopia

Vincent Grafhorst / Dromedary (Camelus dromedarius) caravan transporting salt across salt flat, Lake Asale, Danakil Depression, Ethiopia

Vincent Grafhorst / Namib Sand Gecko (Palmatogecko rangei) in desert, Namibia

Vincent Grafhorst / Namib Sand Gecko (Palmatogecko rangei) in desert, Namibia

Vincent Grafhorst / Namaqua Chameleon (Chamaeleo namaquensis) in desert, Namibia

Vincent Grafhorst / Man looking into crater at night, Mount Nyiragongo, Virunga National Park, Democratic Republic of the Congo

Vincent Grafhorst / Lava in volcanic crater, Mount Nyiragongo, Virunga National Park, Democratic Republic of the Congo

Vincent Grafhorst / Quiver Tree (Aloe dichotoma) group on grassland, Keetmanshoop, Namibia