Įrnafjųršur is located in the bottom of a deep inlet that is also called Įrnafjųršur on the east side of Boršoy.
In 1875 an abandoned Norwegian vessel drifted on shore on Įrnafjųršur. It was loaded with huge amounts of timber. The timber was sold on an auction and due to the large quantities the price for timber decreased significantly. You could by enough timber to build a house for the price of 25 Dkr.
Timber has always been expencive in the Faroes as it has to be imported.