[2] The name of the village translates from the Welsh Y Gilwern (from cil-gwern) as "the recess (or bend) of the alders", probably a reference to its position at the point where the Clydach Gorge opens out into the Usk Valley and the River Clydach flows into a sharp bend in the River Usk.

The church of Llanelly, dedicated to St Elli, is on the hillside above the village, and parts date back to the 12th century.

[5] The Monmouthshire and Brecon Canal, which has a wharf at Gilwern, was built to transport coal, limestone and iron products from the surrounding area using a network of tramways and railroads.

[citation needed] Three local residents were the first to drive over the bridge when it was formally opened, replacing a former junction, at 14.30 hrs., on Thursday, January 26, 2018.

[6] The precast arch over the canal on the Heysham to M6 motorway Link Road was the previous record holder.