Isla Sirena

Isla Sirena is a mysterious island that the crew of the Barnacle encounter is Siren's Song. The island is surrounded by mist and appears to be nothing, but mist when one looks at it through a telescope. Also, the island seems to appear and disappear randomly. The island is located in Davy Jones' locker, but also above air.

The waters around the island are inhabited by at least one sea beast, which Jack Sparrow killed. The island is also home to a group of mermaids who are working for the Sirens.