This ditch barrow on a south-east facing slope below Derk Hill in County Limerick has survived not because anyone went looking for it, but because the ground beneath reclaimed pasture holds its shape with quiet stubbornness, showing up as a cropmark on aerial photographs taken between 2005 and 2012, and again on a Google Earth image from November 2018.

A ditch barrow is among the simpler forms of prehistoric funerary monument, consisting essentially of a low central mound or platform enclosed by a fosse, which is a shallow surrounding ditch, sometimes with an accompanying bank. When the Archaeological Survey of Ireland recorded this particular example in 2007, they found an oval-shaped area measuring roughly 6 metres north to south and 4 metres east to west, enclosed by a fosse between 3.4 and 4.2 metres wide and only about 15 to 17 centimetres deep, with a low bank running from the north-east to west-south-west. A possible causeway, approximately 1.3 metres wide, was noted at the south-south-west, suggesting there may once have been a deliberate entrance point. What makes this site more than a single curiosity is its context: it belongs to a cluster of fourteen barrows concentrated in the southern half of Derk townland, with the nearest example just 12 metres to the south-south-east. The fields around it are crossed by drainage ditches associated with the estate of Derk House, located some 600 metres to the north-east, and a stream 165 metres to the west marks the boundary with the neighbouring townland of Knockderk.

Because the monument is not marked on Ordnance Survey maps, finding it requires some patience with aerial imagery and an eye for subtle ground disturbance. The site sits in what is now enclosed pasture on the slope below Derk Hill, which reaches 781 feet at its summit. The earthworks are extremely slight, with banks and fosse rising and falling no more than about 15 to 17 centimetres, so what is visible on the ground will depend heavily on the season, vegetation cover, and the angle of light. A linear depression running north to south some 30 metres to the east is one of several drainage features in the surrounding fields, and distinguishing archaeological from agricultural earthworks takes some care. The cropmark evidence suggests the monument is best appreciated from above, or at least with aerial images to hand as a guide.