The Hay Railway was a narrow gauge horse-drawn tramway in the district surrounding Hay-on-Wye in Brecknockshire, Wales.

[2] From 1 May 1820, the Hay Railway was joined at its Eardisley terminus, in an end on junction, by the Kington Tramway.

Together, the two lines totalled 36 miles in length, comprising the longest continuous plateway to be completed in the United Kingdom.

[3] The Hay railway operated through rural areas on the borders of England and Wales and was built to transport goods and freight.

c. clxxix) and the line was converted to standard gauge[4] for operation by steam locomotives.