No trace of it remains above ground, and its precise location has never been established. What survives is a single cartographic reference, a plan drawn in 1689 that records the structure at a moment when its purpose was urgent and its future was already uncertain.

The plan in question was produced by Henry Luttrell in 1689 and depicts the town of Sligo along with its defensive arrangements during the Williamite wars, the conflict that erupted across Ireland following the Glorious Revolution and the contest between the Catholic James II and the Protestant William of Orange for the crown. Luttrell's drawing shows a redoubt, a small enclosed defensive work, typically temporary, designed to protect a specific tactical position rather than form part of a permanent fortification. This one was positioned so that its salient faces, the angled forward sections from which cannon could cover the widest possible arc, pointed north, blocking any advance into the town along those two approach routes. When exactly it was built is not recorded. It was certainly in use during the Williamite campaigns of the late seventeenth century, but its construction of earth rather than stone meant it had no long life once the military emergency passed. It was abandoned and eventually removed, leaving nothing to mark where it stood.

Because the redoubt was of earthen construction and has been gone for centuries, there is nothing to see at the site today. The coordinates associated with it are approximate, inferred from Luttrell's plan, and point broadly to the area around the former barracks. The interest here is less in any physical remains than in what the 1689 plan reveals: a town hastily armoured against attack, with temporary earthworks thrown up along roads that are still in daily use.