The longest stair of the Netherlands

The stair at the old coalmine hill Wilhelmina in the South of the Netherlands. It is the longest stair in the country. 507 steps up and what do you think also 507 steps down. :-)
The height difference is 75 m. The highest point is 225 m above sea-level.
In September there is the Caveman run a challenge of climbing the stairs and a hike over the hill of the old coal mine (and more than once).