Gilfach Ddu

[4] Transporting slate from Dinorwic was initially highly cumbersome, involving carting it down a steep road to the nearby Llyn Padarn before shipping it downriver to the sea.

[2] That same year, steam locomotives were introduced within the quarry when an order was placed with the Hunslet Engine Company.

They produced Dinorwic (works number 51 of 1870), which is a clear precursor to the Alice class locomotives that became the mainstay of the quarry fleet.

[8] The original waterwheel that powered the complex was built by the Caernarfon firm of De Winton in 1870, and remained in use until 1926, when it was replaced by a Pelton wheel turbine.

[2]Much of the architecture is of the classical style, though also possessing Gothic decorative elements, particularly for the cast-iron windows that were purpose built for the foundry.

The De Winton waterwheel, which has recently been restored by the National Museum of Wales, is the second largest in Britain at 15.4 metres (51 ft).