The remains of the imposing Fortezza di Albornoz stand on the eastern end of the tuff cliff, leaning against the Porta Rocca or Soliana, and are accessible from Piazza Cahen.
Due to its strategic position of domination and control over the valley of the Paglia river, the fortress was built in the 14th century on commission of Cardinal Egidio Albornoz, legate to Pope Innocent VI. According to historical records, work officially began on 25th September 1364, under the direction of Count Ugolino di Montemarte, a military architect on the payroll of the Commune of Orvieto. The original fortress was a massive quadrangular building with defensive towers on the sides, protected by a moat with two drawbridges. Today, unfortunately, only part of the original perimeter wall remains, along with a tower and the rampart walk.
The Fortress was almost entirely destroyed in 1390 but rebuilt on the ancient perimeter by Antonio da Carpi and in 1527, by order of Pope Clement VII, its water supply was guaranteed by the construction of the famous Pozzo di San Patrizio.
The most recent works commenced in 1888: the moat was filled in and prepared for the construction of the Funicular line and an Amphitheatre for daytime shows. The Fortress is currently home to the Parco Giardino Pubblico di Orvieto (Orvieto Public Gardens), which offers a spectacular view of the valley stretching out endlessly below.