Tromsøysundet

or is a strait located in Tromsø Municipality in Troms county, Norway. The 11 km long strait separates the island of Tromsøya (the location of the city of Tromsø) from the mainland east of the island. The strait is crossed by the Tromsøysund Tunnel (E8 highway) and by the Tromsø Bridge. The strait ranges from about 0.6-3 km wide. The strait connects to the Balsfjorden and Straumsfjorden to the south and into the Kvalsundet and Grøtsundet straits to the north.