Hafnarfjördur is renowned for having one of Iceland's largest colonies of elves, dwarves, and other spiritual beings, that are collectively called "Huldufólk". Centuries-old folklore says that whole families of these beings live in the rocks that are part of the town's center, and we do not doubt it at all.

Though elves are only visible to those with second sight, most Icelanders believe in their existence and there is much evidence to support this belief. In several places, where new roads or housing developments have been built, and workers attempted to move certain boulders or rocky formations, their equipment strangely malfunctioned or even broke down, not just once, but time and again. This happened without any real explanation, and rather than experience expensive repairs, these rocks have repeatedly been left alone and roads made to curve around them, and building plans have been changed.

Local clairvoyant Erla Stefánsdóttir has prepared a map of the Hidden World as revealed to her by the unique residents.