Trollstigen is on the Norwegian County Road 63 that connects the town of Åndalsnes and the village of Valldal, part of the Geiranger-Trollstigen scenic route. It is the most popular tourist road in Norway and definitely worth a visit.
For several hundreds of years there was only a pack road that went over the mountain, but in 1935 the current road was opened after 8 years of work.
An alternative name for it is Trollstigvegen, and from the sources I could find, it might also mean “The Troll’s Ladder” – considering the way the road looks from the side it seems like a very fitting name.
There are a couple of viewing points on the plateau – the most interesting one is a concrete and steel viewing platform that is 200 meters above the road itself, offering a great view of the neighboring mountains.
I visited in 2010, when the plateau had a few wooden huts for souvenirs and a small parking lot. In 2012 a visitor center with a restaurant was opened, to accomodate the growing number of tourists coming here each summer.