The Glyn Valley Tramway was a narrow gauge railway that ran through the Ceiriog Valley in north-east Wales, connecting Chirk with Glyn Ceiriog in Denbighshire (now Wrexham County Borough). The gauge of the line was 2 feet 4+1⁄4 inches (718 mm) while it was horse-drawn, which was unofficially increased to 2 ft 4+1⁄2 in (724 mm) when steam locomotives were introduced. The total length of the line was 8+1⁄4 miles (13.3 km), 6+1⁄2 miles (10.5 km) of which were worked by passenger trains, the remainder serving a large granite quarry and several minor slate quarries.