81° 42' N; long 59° 00' E. Rainer Island has a roughly round shape, with a diameter of 14 km (8.7 mi).

Its highest point is 284 m (932 ft) and it is the summit of the Kupol Vostok Vtoroy (Купол Восток Второй) ice dome that covers the central part of the island.

[1] This island was named by the Austro-Hungarian North Pole Expedition after nobleman Rainer Joseph Johann Michael Franz Hieronymus, Archduke of Austria, Prince Royal of Hungary and Bohemia, also known as the Archduke Rainer of Austria, one of the aristocrats who helped to finance the private venture.

[2] Rainer Island is part of the Zemlya Zichy subgroup of the Franz Joseph Archipelago.

It is located east of Karl-Alexander Island and very close to it, separated by a 2.5 km (1.6 mi) narrow sound.