This substantial earthwork, measuring 16.4 metres east to west, 11 metres north to south, and standing 2.5 metres high, is constructed from dark earth and stones that have weathered centuries of Irish seasons. The mound sits amongst well-maintained agricultural land, though recent activity has unfortunately disturbed its northeastern side, removing some of the original material.

The structure represents one of many prehistoric monuments scattered throughout County Donegal's landscape, though its exact purpose and age remain subjects of archaeological interest. Such mounds often served various functions in ancient Ireland; they might have been burial sites, territorial markers, or ceremonial platforms for communities that lived here long before written records began. The choice of location, near the confluence of two rivers on fertile farmland, suggests this was a significant spot for the people who built it.

This monument was catalogued as part of the comprehensive Archaeological Survey of County Donegal, conducted by Brian Lacey and his team in 1983. Their systematic recording of field antiquities from the Mesolithic period through to the 17th century has preserved vital information about sites like this Lenan mound, ensuring that even as the physical structures face natural erosion and human interference, their details remain documented for future generations to study and appreciate.