The National Museum of the Duchy of Spoleto is located inside the Rocca Albornoz, architectural from fortified rectangular shape having two very broad courtyards, had built on top of the hill of St. Elias from the Spanish Cardinal Egidio Albornoz since 1360 approximately, on the eve of the final return of the papacy from Avignon to Rome, by the will of the popes Urban V and Innocent VI.

Building strategic control of the Via Flaminia, a base and an ideal base for military action aimed at recovering the territories of Umbria, Marche and Romagna, the fortress is the lynchpin of the defensive system of the State of the Church, but it is also conceived as a residential home for the rulers of the Duchy, the governors of the city and the papal legates who will have, among others, the task of administering justice, which will become part of the Rock in prison, and during the nineteenth century finally in prison.
The hill where the building was inhabited since the Bronze Age; Here the Romans built the Acropolis; between the tenth and eleventh centuries there were built two churches, now ruined, St. Mary and St. Elias: it takes its name from the hill.
 
The Museum occupies two wings around the Courtyard of Honour, the south-east and north-east. On the ground floor and the first floor; formally established in 1982 when the Ministry of Justice allowed the transfer of a maximum security prison housed in the historic building.
 
With the gradual dismantling of imprisonment and the gradual recovery rooms and murals that still adorned the walls, the complex rediscovered his articulation of space returning to show all their charms: at this time, to work not yet completed, the project took the form of a collection of materials and works of art, which is already largely kept at the local Museum, that they might witness the origin and development of the entity cultural, political and territorial called up the eighteenth century, the Duchy of Spoleto, founded in 574 by the Lombard conquest and lasting roughly until the end of the thirteenth century.
The Duchy, between the sixth and tenth centuries, occupied the geographical area corresponding to the current region of Umbria, Marche, Abruzzo and also an area of Lazio, at the province of Riet ; absorbed by the state of the Church in the thirteenth century, was partly overlap the territory of the ancient diocese of Spoleto, Spello , which embraced, Terni and Lioness.
The museum, which has taken in setting the design lines drawn dall'archietetto Dardi, aims to illustrate historical events ranging from the fourth to the fourteenth century, the territorial structuring of late antiquity which will take office at the time of construction of the Duchy fortress itself, giving space in particular the testimony of the Middle Ages and through the artifacts displayed either by calling through the educational apparatus as yet remains in the territory.
The exhibition is developed in fifteen rooms and at the same time an integral part of the cognitive process of the Rock. Therefore, the artwork of the museum itinerary is completed by panels that give an account of the historical function of each immediate environment.