Portskewett (Welsh: Porthsgiwed or Porthysgewin) is a village and community (parish) in Monmouthshire, south east Wales. It is located four miles south west of Chepstow and one mile east of Caldicot, in an archaeologically sensitive part of the Caldicot Levels on the Welsh shore of the Severn Estuary. The Second Severn Crossing passes overhead carrying the M4 motorway. The community includes Sudbrook, Crick and Leechpool.
At the eastern edge of the village, in a privately owned field opposite Black Rock Road, very near to the Leechpool turn, is evidence of a significant neolithic chambered tomb or long barrow.