The Barrow Mound

From publisher blurb:

Rising from the low lying mists of some barren heath is the burial chamber of a long forgotten noble.

Lost beneath long grass and choking bracken, the mound resembles nothing more than an unusually hemispherical hill.

Only a single jutting piece of stonework betrays the man-made structure lurking beneath the hill; a narrow outcrop of the crypt through the slotted windows of which it was said the dead could view the world as it grew old...