The rocky island is mostly covered by glaciers, snow and ice. Some small rocky beaches lie on the western and northern sides of the island. There, some grasses, moss and lichens can be found. There are three mountain ridges, with Nemo Peak, 864 m (2,835 ft) high, to the north-west; Nipple Peak to the north-east; and Luigi Peak, 1,415 m (4,642 ft) high, to the south-west. Luigi Peak is the island's summit, despite it never having been completely surveyed. Minor islands surround it, such as Breakwater Island, 33 m (108 ft) high, 8 kilometres (5 mi) north of Cape Astrup, Wiencke's northernmost point. On the south-east coast is Pursuit Point, an Important Bird Area. Near the south-east side is Fridtjof Island, 136 m (446 ft) high, connected to Wiencke by a chain of small rocks and islets. In the vicinity of Cape Willems, the south-easternmost extremity of Wiencke, are the Bob Islands, three in number, of volcanic origin, up to 134 m (440 ft) high.
The island seems to have been discovered first by Edward Bransfield on board the brig Williams in January 1820, though he named it a cape. In 1829 Henry Foster (scientist) sailed around the island. In 1873 the German Eduard Dallmann was the first to land on the island, and reported it 'a lonely place'. The island was named by the Belgian Antarctic Expedition, 1897–99, under Adrien de Gerlache, for Carl August Wiencke, a Norwegian seaman who fell overboard and lost his life on the expedition.
Britain set up bases on Deception and in a bay of Wiencke Island in 1944 and another at Hope Bay in 1945, to do weather reporting and to check that there was no German naval activity. Only one of these three bases remains, on Goudier Island in the bay of Port Lockroy, off Jougla Point, near Wiencke Island's south-western end.
An Argentinean light tower was installed in 1947 at Py Point at the southwest end of the Peltier Channel on nearby Doumer Island, and a refuge hut erected in Dorian Bay in 1957, north of Port Lockroy. British Antarctic Survey (BAS) erected a staging hut, known as the Damoy Point refuge, near this Argentinean refuge in 1975 to act as a base for a temporary summer aircraft ice-strip. This was taken out of use in 1995, and stands restored as a historic site.
Another scientific station (Yelcho) was established in 1962 by the Chilean Navy in South Bay on nearby Doumer Island. An emergency shelter was built in 1957 in Alice Creek 150 m south of Goudier Island on the east coast of the island, followed two years later by a larger hut, for use when maintaining a low-frequency electromagnetic aerial and remote receiving equipment. These two huts were removed in 1996 when derelict while Base 'A' on Goudier Island was restored.