Spikeroog is one of the smaller islands of the Skellige archipelago. It lies to the west across the Allenker sound from the main islands of Ard Skellig and An Skellig. There are two villages on the island: Svorlag and Hov.
The name "Spikeroog" is most likely inspired by the German North Sea island of Spiekeroog.
Located West of Udalryk's Longhouse is a Place of Power. It can be reached with some jumping against the snowy stones next to the longhouse until Geralt manages to scramble up. Or once inside the house go down to the far western side and then on the left where a piece of old cloth hangs from a collapsed ceiling and beams against the wall, Geralt can jump up through there to get outside and follow the path to the place of power.