Friedrich Gerhard Rohlfs (April 14, 1831 - June 2, 1896) was a German geographer, explorer, author and adventurer.
He was born at Vegesack, now part of Bremen. There was much pressure on Rohlfs to be in the medicine field, and he eventually joined the French Foreign Legion in a medical capacity. Serving for some time as a personal physician to a Moroccan nobleman, he eventually set off on his own, exploring the oases of Morocco. It was on this trip that he was attacked and left for dead, his leg almost severed from his body. These injuries would keep him from returning to Europe for most of his life; the cold weather somehow aggravating them. After this trip, Rohlfs was the first European to cross Africa north to south. His route took him from Tripoli through the Sahara desert, over Lake Chad, along the Niger River to the Gulf of Guinea from 1865-1867. He was the second European explorer to visit the region of the Draa River in the south of Morocco.
In 1874 Rohlfs set out from Dakhla Oasis intending to reach Kufra. In February he was c. 100 km north of Abu Ballas (Pottery Hill) in the Western Desert. Accompanied by Karl Zittel and a surveyor called Jordans, Rohlfs and his colleagues experienced a downpouring of rain - a rare occurrence in the desert, seemingly only happening every twenty years. Rohlf's team restocked and watered their camels and left a cairn at the place he had named Regenfeld (Rainfield).[1]