According to `` Guinness World Records '' ( `` GWR '' ) , Vatnajökull is supposedly the object of the world 's longest sight line , from Slættaratindur , the highest mountain in the Faroe Islands .
According to Guinness World Records Vatnajökull is the object of the world 's longest sight line , 550 km from Slættaratindur , the highest mountain in the Faroe Islands .