The site at Linsfort consists of a roughly rectangular platform measuring 18.5 metres from east to west, defended by an earthen bank that incorporates stone elements within its construction. What makes this particular fortification intriguing is its strategic position; the promontory naturally drops away steeply on all sides, creating a formidable defensive position that required minimal human modification to become virtually impregnable.

Access to the fort was strictly controlled through a single, deliberately narrow causeway approaching from the southeast. This artificial construction, approximately 2 metres wide, was engineered with precision to make any assault extremely difficult. The causeway drops 2 metres on its southwest side and a more dramatic 4 metres on the southeast, creating a bottleneck that would have left any attackers exposed and vulnerable. This type of coastal promontory fort is characteristic of Iron Age defensive architecture in Ireland, where natural topography was cleverly incorporated into military design.

The fort's location overlooking Lough Swilly would have provided its inhabitants with commanding views of maritime traffic along this important waterway, whilst the steep drops and narrow access point offered security from raids. Though time has softened its earthen ramparts, the essential structure remains clearly visible, offering visitors a glimpse into how ancient communities balanced the need for defence with the advantages of coastal living and trade.