The southeast-northwest oriented Portal Tomb of Newmarket, located in the townland of Newmarket (in Irish, Baile Roibín), south of Hunter’s Wood in Romansvalley, is the northernmost of the partially preserved Portal Tombs in County Kilkenny, Ireland. Portal Tombs are megalithic structures found in Ireland and Britain, consisting of two equally tall, upright stones with a doorstone in between, forming the front of a chamber covered by a partially massive capstone.

The tomb is situated on a low oval mound measuring approximately 10 meters in diameter. Most of the stones from the rear part and the capstone are missing. Similar to the Portal Tomb of Taylorsgrange in County Dublin, only the two flat portal stones and the doorstone remain, positioned opposite each other. The portal stones are approximately 2.3 meters high, and the doorstone stands at 1.4 meters in height.

On the eastern slope of Tory Hill in Farnoge, the Court Tomb of Farnoge can be found, the only Court Tomb in Kilkenny.