That asymmetry is not the result of damage or erosion but of deliberate placement, the mound built across a break in the slope so that it reads differently depending on the angle from which you approach it.

This is a mound barrow, a type of prehistoric funerary monument common across Ireland and Britain, in which earth and sometimes stone were heaped over a burial or series of burials. The Knockbower example has a summit diameter of roughly 8 metres and a base diameter of approximately 14 metres, dimensions that suggest a reasonably substantial construction effort, though nothing exceptional by regional standards. What is more intriguing is the possible boulder kerb visible at the base of the mound. Kerb stones, where they survive, were used to retain the mound material and often to mark a boundary between the monument and the surrounding landscape, sometimes carrying symbolic as well as practical weight. Whether the boulders here formed a continuous kerb or are simply loose stones that migrated downslope over the centuries has not been firmly established.