First underwater roundabout (traffic circle)

The first underwater roundabout is located beneath the waters of the Skálafjørður, a fjord that splits the island of Eysturoy in the Faroe Islands (part of the Kingdom of Denmark). It was built as part of a major engineering project called the Eysturoyartunnilin ("Eysturoy Tunnel"), which provides a road link between the towns of Runavík and Strendur (located on opposite sides of the Skálafjørður on Eysturoy) and the Faroese capital of Tórshavn, located across the Tangafjørður sound on the island of Streymoy to the south. The tunnel opened to the public on 19 December 2020.

The roundabout is located under the mouth of the Skálafjørður, at a depth of around 70 metres below sea level. The Eysturoyartunnilin descends to a depth of 189 metres below sea level during the trip from the roundabout to Tórshavn. The construction of this tunnel cut the journey time from Tórshavn to Runavik from more than an hour to just 16 minutes. Construction began on 21 February 2017, and the tunnel boring was completed on 3 June 2019. The roundabout is home to an installation comprising a group of moving sculptures created by local artist Tróndur Patursson.