On a slight rise in the Curragh, one of Ireland's most historically layered stretches of open grassland, a low earthwork traces a near-perfect circle in the ground. It would be easy to walk straight past it, and most people do.

The feature is a ring-ditch, a type of monument consisting of a circular area enclosed by a shallow fosse, which is simply a ditch, with a low bank running along its outer edge. This particular example measures sixteen metres across the enclosed interior, with an overall diameter of twenty-seven metres when the fosse and bank are included. A gap on the western side marks what appears to be an original entrance. Ring-ditches of this kind are generally associated with prehistoric funerary or ritual activity, sometimes representing the ploughed-down remains of a round barrow, a burial mound whose central earthen heap has long since been levelled by centuries of cultivation or grazing. The site was recorded by Seán P. Ó Ríordáin, the influential Irish archaeologist, in 1950, where it appeared as Site G1 in his survey, accompanied by a scaled cross-section running north to south.