What locals once called the Giant’s Grave appears on early Ordnance Survey maps from the 1830s and 1840s, first labelled as Giant’s Rock, then later as Giant’s Grave. Today, the site has been heavily quarried and overgrown, with only two large prostrate slabs remaining about 6 metres apart at the southern edge of the quarried area, each roughly a metre across. Whether these formed part of the original ancient structure remains unknown.

Thomas Fagan, writing between 1845 and 1848, described what he called ‘the ruins of a pagan sepulture’ at this spot. According to his account, the structure measured about 2.75 metres by 1.5 metres and consisted of large stones between 0.6 and 1.2 metres high, set on end and edge in the ground. At that time, only three stones remained standing; one on the south side stretched an impressive 2.4 metres long, whilst two smaller stones completed the arrangement. Fagan noted several prostrate stones nearby, including one massive slab measuring 2.4 metres long, 1.2 metres broad, and 0.45 metres thick, which he believed had once rested atop the upright stones as a capstone. About 19 metres to the east, he recorded another large slab, nearly 3 metres long and 2 metres wide, resting on a smaller stone, possibly the remains of a second burial structure.

The fate of these megalithic remains was sealed sometime before 1904, when the landowner, a Mr Houston, removed the large stones that had comprised the feature, though the exact date of their removal went unrecorded in the Ordnance Survey Name Book. Archaeological monitoring in 2001 during construction of a house, access lane and septic tank near the site turned up no archaeological materials or remains, leaving the true nature and significance of the Giant’s Grave to speculation. Whether it was indeed a megalithic tomb, as many similar structures in County Donegal suggest, or served some other ancient purpose, the Giant’s Grave at Gortree remains an intriguing footnote in Ireland’s prehistoric landscape.