The steps that run alongside the Niesenbahn Funicular Railway in Switzerland comprise the longest stairway in the world. There are 11,674 steps in all, and it's only possible to hike them one day a year during the Niesen Run. Registration is required and is limited to 500 participants. It's a total distance of 3.4 km but its vertical is 1,669 m, just over one mile.

Construction of the line commenced in 1906, and it opened in 1910.

The funicular railway operates from May until November and is a two-part, 30-minute ascent. The steps and railway culminate at the Berghaus Niesen Lodge. It has a restaurant where you can dine atop a mountain peak overlooking some of the most picturesque vistas in the world. The staircase produces an amazing optical illusion. When you look at the staircase, the steps seem unending as far as the eye can see.

It has been certified as the world's longest staircase by the Guinness Book of World Records.

More Info: www.curiousatlas.com