
Taken by lying flat on the road below the car park. The aperture is now so tiny that this is almost the extinction angle. However, the original level of the hill may have been lower than the road surface!
Image credit: © Royston E Naylor
Taken by lying flat on the road below the car park. The aperture is now so tiny that this is almost the extinction angle. However, the original level of the hill may have been lower than the road surface!