Upturned Pillbox, Happisburgh Beach, Norfolk

An empty beach in September under a sky promising rain.

The cliffs here are composed of glacial "tills" separated by layers of stratified silt, clay and sand. They have been eroding for the last 5,000 years when sea level rose to close to its present level.

In winter erosion is caused by groundwater running down the cliff face. In summer the beach is higher and waves attack the base of the cliffs.

In front of the cliffs is an upturned pillbox, from the top of the cliff, which has toppled down in one piece.

This is a Type 22 pillbox designed as a regular hexagon with embrasures on five sides and an entrance on the sixth protected by a Y shaped anti-ricochet wall.

In the Second World War the beaches on the Norfolk coast were defended with mine fields, barbed wire, tank traps and pillboxes.