What survives today are the foundations of a structure that once stretched 24 feet in length, with walls measuring just over 6 feet thick; substantial fortifications that speak to the uncertain times in which they were built. Though these ruins aren't visible at ground level anymore, archaeological surveys have mapped out their footprint, preserving the memory of what once stood here.

The castle's history comes into sharper focus through the Civil Survey of 1654-6, which recorded the site as consisting of 'a castle and some thatch cabins'. This brief description offers a glimpse into the social structure of 17th century rural Ireland, where the stone castle of the local lord stood alongside the humble thatched dwellings of tenant farmers and workers. By the time of the survey, conducted during the Cromwellian period, the castle may already have been in decline, though it still commanded enough importance to warrant documentation.

The archaeological record of Monroe Castle was formally documented by Jean Farrelly and Caimin O'Brien in their comprehensive inventory of North Tipperary's archaeological sites, published in 2002. Their work, building on earlier Ordnance Survey letters from 1930 by O'Flanagan, has ensured that even though the castle's stones have long since disappeared into the landscape, its place in Ireland's medieval heritage remains recorded for future generations to discover and explore.