 The Sweden-Finland border on Märket is marked with holes drilled to the rock, because seasonal pack ice can shear off any protruding markers.In folklore, a type of haltija, "rajahaltija", a kind of a local spirit, was believed to haunt borders that had been unjustly moved.The earliest reference to a boundary stone in Greek literature is in the "Iliad", which describes the goddess Athena using one as a projectile.