The find was not the result of planned excavation or archaeological investigation, but of routine agricultural work reshaping the ground, which means its full extent and character were never formally recorded before it was disturbed.

The passage came to light immediately south of a ringfort that had already been levelled, alongside a separate souterrain, the term for an underground stone-lined tunnel typically associated with early medieval settlements in Ireland, often used for storage or as a place of refuge. A ringfort, to place the wider context, was a circular enclosed farmstead, usually defined by earthen banks and ditches, common across Ireland from roughly the sixth to the twelfth centuries. That both the ringfort and a known souterrain had already been removed or damaged before this timbered passage emerged suggests the site at Knockglass had seen repeated disturbance over time, with each episode erasing a little more of whatever complex originally stood there. The use of timber rather than stone as a covering is relatively unusual; most surviving Irish souterrains are roofed with stone lintels, making the Knockglass account, if accurate, a notable variation, though without systematic excavation the description remains based on local recollection alone.