Cair Andros, the Ship of Long-foam, was a long island in the Anduin north of Minas Tirith, shaped like a great ship with its prow breasting the current, and held by Gondor as a fortress guarding the river-crossing into Anorien. In the War of the Ring Sauron's forces stormed and took it to open the northern way against Gondor; it was retaken after the fall of the Dark Lord.