Koldewey  Karl 
(26.10.1837–17.05.1908)

German traveler. 
Born in Hannover. Educated first at the Hannover Polytechnic, in 1867 he graduated from the University of Göttingen. He made his first voyage in 1853. 
In 1868–1870 Koldewei made two voyages in order to reach the North Pole between Spitsbergen and Greenland. 
The initiator of these expeditions was the German geographer A. Peterman, the author and promoter of the hypothesis of the existence of the open sea in the polar space. He believed that it was only necessary to break through the ice barrier lying north of Spitsbergen, and then the path would be free. Mastering this route promised huge material benefits, and Germany, which for many years stood apart from the Arctic problems, decided to send an expedition led by Koldewei. 
The expedition vessel, a small yacht “Germany”, left Bergen on May 24, 1868 and headed to the east coast of Greenland. At 120–130 km from Greenland, in the region of 75° N, they entered the ice. After several vain attempts to break through to the north in this area, Koldewei went to Spitsbergen and in the middle of September tried to go north from there. He managed to reach 81° 04′N. Winter was coming, and Koldewey hurried back. 
Failure did not shake Peterman, and he found funds for organizing a second, more ambitious expedition. They built the steamer "Germany", which was attached to the sailing vessel "Hansa", re-equipped for navigation in ice conditions. 
Peterman believed that the best ice conditions should be between Spitsbergen and Novaya Zemlya, and offered to send one of the ships there. However, Koldewei categorically opposed this and, going to a conflict with Peterman, sent both vessels on last year’s route to the east coast of Greenland.

Under 74° 04′ N in an impenetrable fog, the ships lost each other and never again met. Squeezed with ice, the “Hansa” was swept away to the south and crushed at 70 ° 52 ′ N. The crew, disembarking on an ice floe, drifted along the eastern coast of Greenland for 200 days and then reached the south-western coast with great difficulty on boats. "Germany" managed to reach the coast of Greenland and cross the latitude of 75° , where the expedition stopped for the winter. One of its participants, later famous Yu. Payer, undertook a luge ride along the coast. Having risen to a height of 1220 m, he saw the sea covered with ice to the horizon. On the next trip, Koldewey and Payer reached 77° latitude and only solid ice was also seen from a height of 300 m. An important achievement of the second expedition Koldevey was clarifying the configuration of the northern coast of Greenland. 
Both expeditions of the Koldewei showed the inconsistency of Peterman’s hypothesis, which, however, remained self-righteous for a long time, becoming the initiator of the subsequent expeditions of Payer - Weyprecht and De Long. 
In 1871, Koldewey became an assistant at the Hamburg Marine Observatory, where he processed the meteorological and hydrographic results of the expeditions. When founding the Imperial Naval Observatory in Germany, he was appointed head of the department. 
He died in Hamburg. 
Island in the archipelago of Franz-Josef Land. Opened and named in 1874 by Yu. Payer. 
Island (Big Koldevey) near the coast of East Greenland. Discovered in 1870 by the Koldevey's expedition.

Cape (Koldevey) in the southwest of the Beich Peninsula on the east coast of Ellesmere Island in the Canadian Arctic Archipelago.

Cape (Kapp Koldewey) on the west coast of Wilhelm Island in the Hinlopen Strait.      The coordinates are 79° 00'N    20° 00'E.