1) Built 1814 over waterfall; showing signs of decay. JAH, 09/01/2003

2) The tramroad was built in 1815 by a company named 'The Brinore Tram Road' to take coal, lime and iron (from Union Ironworks near Rhymney) to the Brecknock and Abergavenny Canal at Talybont. The engineer was George Overton. The tramroad closed c1890 after a lengthy period of decline, especially after the Merthyr & Brecon Railway opened in 1866.

The route around Blaen Dyffryn Crawnon was always known as the most precipitous part of the route, where the tramroad could be made only by cutting a ledge into the steep slope.

The culvert under the tramroad carried a fast stream, with waterfall on downhill side. All that survives is stone footings of a lined channel. This culvert has been replaced by a modern wooden footbridge supported on concrete plinths.
Recorded as part of Uplands Initiative Survey. W B Horton, H&H, 6/11/2006.