Kaer Trolde is a harbor town reigned over by jarls from Clan an Craite on the coast of Ard Skellig, the largest of the Skellige islands, and appears as black and shapeless as some great marine crustacean thrown out by the waves. It's built just under the island's main stronghold whose highest towers make the entire archipelago visible.
The town port serves as the docks for the Jarl of Skellige's fleet and is accessible by longships and triremes. and is home to many sailors, fishers, and warriors but also alchemists, goldsmiths, glass blowers, and jewelers. The island branch of a dwarven Cianfanelli Bank is also situated here.
According to legend, Grymmdjarr, the founder of Clan an Craite, carved the keep that overlooks the town with his bare hands.
- A tapestry in the Kaer Trolde throne room depicts warriors battling the Ice Giant. Its style makes reference to an actual 11th century artifact, the Bayeux Tapestry, which shows William the Conqueror’s successful battles for control over England. 
- Kaer or Kêr means city in Breton, the real world language of Brittany.
- In The Witcher 3: Wild Hunt, developers made an error. Kaer Trolde is depicted as a town in the novels, but the developers treat it like it's the keep that overlooks the harbor.