Rain carved a Madagascar hillside into a forest of stone razor blades
Madagascar's Tsingy de Bemaraha formed as ancient seabed limestone, laid down around 200 million years ago, was slowly dissolved by rainwater seeping into vertical cracks. Over millions of years those cracks widened into a maze of knife-edged pinnacles so sharp that 'tsingy' means 'where one cannot walk barefoot.' The UNESCO-listed reserve now shelters lemurs and other species found nowhere else on Earth.