High Fell Quarry, above Tilberthwaite, reveals the volcanic origins of Lakeland slate. Quarry working restarted under a new tenant in 2023. Climbing advice warned of intended renewed blasting and advised people to keep away. Stay on public paths and out of the workings; seek the landowner’s permission before any proposed quarry visit or sampling. Ordovician, Disused Quarry, Rating: ♦♦♦