Though its exact location has been subject to some historical debate, archaeological surveys from the 1980s and 1990s have helped pinpoint its approximate position. The castle takes the form of a tower house, a type of fortified residence that became widespread across Ireland from the 14th century onwards, particularly favoured by the Anglo-Norman and Gaelic Irish nobility for their defensive capabilities and relatively modest construction costs.

Tower houses like Moyle Castle typically featured thick stone walls, narrow windows, and multiple storeys accessed by spiral staircases built into the walls. These structures served dual purposes; they were both defensive strongholds and symbols of lordly authority over the surrounding landscape. The castle would have controlled local trade routes and agricultural lands around Dundalk, positioning its owners as significant players in the complex political landscape of medieval Louth.

Historical records mentioning Moyle Castle are somewhat sparse, though it appears in various archaeological inventories compiled throughout the 20th century. The Archaeological Survey of County Louth, published in 1991, along with earlier work by researchers like Gosling, have documented the site’s significance within the broader context of Louth’s medieval heritage. These surveys, regularly updated with new findings, continue to shed light on the castle’s role in the county’s turbulent history, from the Anglo-Norman invasion through to the plantation period and beyond.