The Ruff lek on Langvassmyrane is the only known phenomenon of its kind on Hardangervidda. Every year it attracts hens from the whole plateau. The marsh is also the richest wetland in the county. This green oasis is located in a rocky moraine landscape a few hours walking distance south of Dyranut.
After the ice age, Granvin Fjord reached all the way up under Skjervsfjossen waterfall. Just a thousand years later, as a result of the rising of the land after the ice melted, this whole inner part of the fjord freed itself of the sea and became Granvinsvatnet lake. In spite of this rise in elevation, this waterway is still navigable for fish: Sea trout have wandered into Granvinsvatnet in more recent times and evolved to become freshwater trout. And salmon and sea trout made the journey 13 kilometres up the Storelvi river.
When the lush beach area innermost in Ulvikapollen was protected, the bird life was instrumental to the decision. The plant diversity is just as impressive. In Hordaland sea meadows such as this are rare small in size - they are more common in coastal environments.