at the end of the last Ice age, between 15,000 and 10,000 years ago, a recent event in geological timescales. At that time most of what is now the North Sea was dry land, with the Rhine and the Thames combining to form a giant river estuary. As the ice melted, the sea level rose and the North Sea was formed. Since then, Beeston Bump has been eroded by the sea: most of its seaward side had been washed away by the 1930s. Almost 90 yards (80m) of the cliff have now been lost to the sea, along with a brickworks which stood to the east of the summit and a football pitch. In recent times, coastal erosion has been slowed by building groynes and sea walls along the coast and below the hill. During low tides on the foreshore of the sandy beach beneath Beeston Bump, one can find the curious paramoudras and flint circles. These are sometimes mixed in with the exposed "Beeston Chalk". In Norfolk, paramoudras are known as "pot stones", due to the shape. Local folklore tells of the southern slopes of the Bump being festooned with grapevines, tended by the monks of the priory. The Bump can be climbed using the North Norfolk Coastal Path from either the east or west, and is well worth the climb. From the top, there are views of the surrounding land and sea. Each Easter, the combined churches in the area make a pilgrimage carrying a cross to the top of Beeston Bump, and an open-air service takes place. Beeston Hill Y-Station During the World War II Beeston Bump was the location for one of the network of Signals Intelligence collection sites: Y-stations. These stations collected material to be passed to the War Office's Government Code & Cypher School at Bletchley Park. There were several of these stations around the east coast and by triangulating the signals, the exact location of enemy shipping could be pinpointed. In an episode of the BBC1 series Coast, the technique was explained and demonstrated. In the same programme, Joy Hale was interviewed by the presenter, Hermione Cockburn. Hale had been a Wren and an operator at the Y-station. The concrete remains of part of this facility can still be seen on the summit of the hill: the octagonal concrete base measures 3.85 m (13 feet) across, with a channel running west to east