aberdyfi abergynolwyn aberllefenni slate quarry alfred mcalpine anglesey anglicanism apprenticeship baron penrhyn betws-y-coed blaenau ffestiniog braichgoch slate mine brass band bryn eglwys caernarfon cambrian canals of the united kingdom cardiff centre for alternative technology coal mining conwy valley line corris corris railway criccieth crown land de winton denbigh dinorwic quarry disestablishmentarianism dublin eisteddfod electricity ffestiniog railway german empire great depression hamburg headstone hydroelectricity hydropower kate roberts king arthur laser line shaft llanberis llangollen llechwedd slate caverns llechwedd quarry london and north western railway mabinogion machynlleth maentwrog mechanization menai strait minutes moelwyn bach nantlle railway nantlle valley narrow gauge railway national library of wales national slate museum net profit nonconformism ordovician padarn railway pembrokeshire penrhyn quarry penrhyn quarry railway port penrhyn porthmadog portugal protectionism quarry recession rhuddlan river dwyryd river dyfi roman britain roof shilling shipbuilding silicosis silurian slate slate industry slate waggon snowdon steam engine strike action strike pay taliesin talyllyn railway tile ton tory trade union traed mewn cyffion vaynol wales wales millennium centre water wheel welsh language welsh literature world war i world war ii y felinheli