Navan Fort in Ireland is an archaeological site of national and international importance. During 1998 a portion of the ditch surrounding Navan Fort in Ireland was excavated by archaeologists from Queen's University Belfast. In 2001 the author was tasked with analysing the ditch wood and artefacts recovered during this excavation. By extension, this also of necessity included analysis of the previous excavations at this site, and in particular the 40-metre structure there. This analysis extended to consideration of possible Roman influences, and, of arguably far more importance, the implications for our Irish heritage. Much of the research published here was conducted towards a dissertation for an MA in Archaeology (2001) at Queen’s University Belfast. A decision was taken to publish it now due to some important observations concerning possible Roman influences at this archaeological site. Also due to publication by this author of Early Byzantine Ireland: a survey of the archaeological evidence (2021), which reveals further evidence of Roman or Byzantine artefacts recovered in Ireland. There is also some evidence that the topography of Navan Fort as described in the ‘Ulster Cycle’ bears an uncanny resemblance to Rome during the Republic.