Hornindalsvatnet is Norway's and Europe's deepest lake, and the world's thirteenth deepest lake, officially measured to a depth of 514 metres (1,686 ft). Its surface is 53 metres (174 ft) above sea level, which means that its bottom is 461 metres (1,512 ft) below sea level.

The deepest point of the lake was explored using a ROV (remotely operated vehicle) in 2006. A small white fish was discovered on the lake bottom – probably a new species of Arctic charr (Salvelinus alpinus). It was previously also located in Lake Tinn, Norway's third deepest lake.

The lake is also the site of the Hornindalsvatnet Marathon, held annually in July.

More Info: en.wikipedia.org