What is the name of the port city of Gondor on the Anduin?

The port city of Gondor on the Anduin is Pelargir. It stood in Lebennin, near the river’s lower reaches, where the Sirith joined the Anduin before the river reached the Bay of Belfalas.

Pelargir was founded in the Second Age by the Faithful Númenóreans. It became one of Gondor’s most important military and commercial ports, serving as a base for royal fleets and as a gateway between Gondor, the coast, and the lands farther south. Its name is often translated as relating to the ships of the king.

Pelargir is easy to confuse with Dol Amroth, another important Gondorian port city, but Dol Amroth lies on the coast of Belfalas rather than on the Anduin. Umbar is also a major port, yet it became a stronghold of the Black Númenóreans and Corsairs, hostile to Gondor for much of its history. Edoras, meanwhile, is the inland capital of Rohan.

During the War of the Ring, Corsairs captured Pelargir. Aragorn, the Grey Company, and the Army of the Dead retook it, then sailed north in the captured ships to help defend Minas Tirith.