[2] In 1870 there were calls for a railway station to be built at Pennal, partly in anticipation of the output of Cwm Ebol.

[13] Evan Jones, the quarry manager was subsequently fined £2 10s (equivalent to £266 in 2018) for not properly enforcing the blasting rules.

[17] During the 1860s, slate from Cwm Ebol was carted to a wharf at Llyn y Bwtri, on the north bank of the Afon Dyfi, to the south of Pennal.

[19] The tramway was originally built to 3 ft (914 mm) gauge, both internally within the quarry complex, and for the longer line which was nearly 2 miles (3.2 km) long.

[20] It originally crossed the Machynlleth to Aberdyfi road at Pennal to reach the river wharf.

It was the last Welsh slate quarry connected only to a trans-shipment point instead of directly to a railway or to a sea port.

The reservoir provided water to power the mill machinery in the quarry, initially by waterwheel and later using a Pelton wheel.

600 residents of Pennal and surrounding houses were evacuated, and a controlled release of water took place to reduce the level in the reservoir.