Look down on a needle of chalk a novelist swore was hollow

A spike of white chalk stands in the sea off Étretat, on the Normandy coast, beside an arch at the end of the cliff. From the beach it is a rock in the water. From above it is the best view on the coast.

The way up is the path along the top of the western cliff. It leaves the town and climbs, and the coast comes into view one piece at a time: the needle, the arch beside it, and then a second, wider arch further on.

From the top the needle is below rather than in front, and the whole run of cliff, arches and sea is in one frame: white chalk going straight down into green water.

In 1909 Maurice Leblanc published a novel in which the gentleman thief Arsène Lupin discovers that the needle is hollow, with the treasure of the kings of France inside, and gave it more than eighty meters. In 2012 the astronomer Donald Olson measured it at 54.5 meters above its base at the lowest tide. It is not hollow.