CAPE CALENCIA
"The remnants of Hyperborean settlements can be found about the cape.
These ruins are from immemorial times long before the ad-
vent of the Ashen Worm, the rise of the orthodoxy of
Xathoqqua, and the arrival of the barbaric races. Most
such ruins have been reclaimed by the forest, though
small family groups of Carolingian Franks are reputed
to build on these ruins."

This is not specifically mentioned in The Ghost Ship of the Desert Dunes, where
else can it be found?