A crystal clear river is so clean that the 50ft deep riverbed can be seen from a bridge crossing over the water.
The 30km long Verzasca River in Switzerland is renowned all over the world for its clear turquoise waters.
But while pictures of the sparkling waters are often taken from the mountains surrounding the river or from bridges crossing over it, it’s much rarer to see photographs taken from the bottom of it.
The highest point is dependent upon the definition of Europe. Considering Europe as an abbreviation for the European Union, the highest point is Mont Blanc, on the border between France and Italy (4,810 metres; 15,781 feet).
Highest attainable by transportation – Cable car (and lift) Klein Matterhorn, Switzerland (3,883 metres; 12,736 feet)
Aareschlucht, Switzerland is a section of the river Aar that carves through a limestone ridge near the town of Meiringen. This is an indirect product of glaciation; 10,000 years ago, just as the Ice Age was coming to an end, torrential runoff water from melting glaciers eroded a deep, narrow chasm through the limestone barrier. Although barely one mile long, this passage is bordered by sheer cliffs up to 165 feet (50 m) high on either side. At the bottom of this steep drop the river is only a few metres wide.