GeoGraph - photograph every grid square

Incombe Hole, Ivinghoe

Incombe Hole is the steep-sided dry valley in the middle part of the picture. It would have been created in glacial times when the chalk was fractured by water freezing and thawing in its pores and joints in consequence of which there would have been a downhill movement of the debris. The summit in the background is Hastoe Hill which at 803 feet is the highest point in Hertfordshire.