USK, (Monmouthshire) near the conflux of the Usk r. and Byrdhin, 108 cm. 130 mm. from London, had once a priory, and a large castle, situate bet. the Usk r. and the brook Oilwy. The Mt. is on M. Fairs May 1, Trinity. M. and October 16. The Usk r, runs through the middle of the Co. to the Severn.