Adventfjorden (Advent Bay) is a 7 km long and 4 km wide bay on the southern side of Isfjorden, on the west coast of Spitsbergen. The name is a corruption of Adventure Bay, which was probably named after the Hull whaleship Adventure, which resorted to Isfjorden in 1656. The fjord was originally known as Klass Billen Bay. At the head of Adventfjorden is Adventdalen.

Adventfjorden (Advent Bay) is a 7 km long and 4 km wide bay on the southern side of Isfjorden, on the west coast of Spitsbergen. The name is a corruption of Adventure Bay, which was probably named after the Hull whaleship Adventure, which resorted to Isfjorden in 1656. The fjord was originally known as Klass Billen Bay. At the head of Adventfjorden is Adventdalen.