The Citadel was the top layer of Minas Tirith, within the seventh wall. Within the citadel was the White Tower of Ecthelion, which housed the Tower Hall. Several other buildings were located here as well. The Citadel would have been around five hundred feet across.
In the center was the White Tower, rising to a great height. Behind was the large sprawling King's House, where the Kings of Gondor once lived. In front of the tower was the Place of the Fountain, a courtyard containing the White tree and a central fountain. The Citadel was accessed via a wide tunnel through the hill that led to a small gate. The wide cliff narrowed to its point around two hundred feet beyond the Citadel. As with all the city's levels, the Citadel had a high wall and seven towers.
Probably the most important symbolic area of the city, the Place of the Fountain was the home of the great White Tree. It was a large circular grass area, around 50 feet wide, with the White Tree being the central feature. The fountain was positioned some way before the tree. It flowed into a small pool, then back round to the fountain. The Tree symbolised Gondor, and was the flag and emblem of the City Guards. The Tree was grown from a seed of Nimloth, the tree given to the Númenóreans by the Eldar. It was planted by Isildur, and grew to symbolise the blessings of Men. But in the third age the tree was withered, perhaps symbolising Minas Tirith's decline. It was only with the crowning of Aragorn Elessar that a new sapling was founded, showing the City's rise to glory under the new King.