Carlisle to Penrith Joining the cracker packers of Carlisle on the factory floor, Michael really takes the biscuit as he investigates the Victorian appetite for the custard cream on his new journey through north-west Britain. Braving a perilous descent into the only operational slate mine in England, Michael discovers a miniature railway which once hauled slate to the surface. Following in the footsteps of Victorian miners on their way to work, he steps out gingerly on to what is now Britain's only Via Ferrata - a terrifying tightrope challenge 300 feet above the Borrowdale Valley.