Minas Tirith is the capital city of Gondor in J.R.R. Tolkien’s writings.
The city stands on the eastern side of the White Mountains and becomes Gondor’s principal seat of government after the decline of Osgiliath. Its name means “Tower of Guard” in Sindarin. Tolkien describes it as a city built in seven levels, rising against the mountain of Mindolluin and protected by walls, gates, and the Tower of Ecthelion.
In The Return of the King, Minas Tirith is threatened by the armies of Mordor during the War of the Ring. The Siege of Gondor culminates in the Battle of the Pelennor Fields outside the city. Aragorn later enters Minas Tirith as the returning king, while the city remains central to the restoration of Gondor.
Minas Morgul is a different city, the corrupted former Minas Ithil, and Osgiliath was Gondor’s earlier capital. Edoras is the capital of Rohan, so these names are not interchangeable.