The Castello di Celano is generally known as “Castello Piccolomini”: this denomination emphasizes a 15th century adaption of the architectural complex, In reality the first phase of the construction came about, most probably, around 1392; on this date, in fact, the Count of Celano, Pietro Berardi, ordered the construction of the Chiesa di Sant’Angelo and of the ancient convent of the Celestini, donating this ancient palace to the monks. It is presumed, therefore, that the moment the Count left his old residence, the construction of the new castle on the top of the S. Vittorino hill had already begun.
In this first phase the walls and the first two floors of the donjon keep up to bottom of the string course cornice had been built.
In order to have further information about the castle, it is necessary to wait for the marriage of Countess Iacobella, Pietro’s niece, to Lionello Acclozzamorra, who resumed the construction of the building in 1451, almost completing the work with the achievement of the piano nobile, of the route of the rounds and of the four corner towers.
Despite the two phases of construction gave the castle diverse characteristics of style, the building presents itself in such a compact and harmonious way that the works carried out in a second phase seemed to be part of the initial project.
Acclozzamorra perhaps had the angular towers lowered, seeing that the medieval construction standards had changed according to the evolution of the offensive weapons, and carried out the apparatus to rise with the rounds route above it at an equal height along the entire perimeter of the building, to facilitate the movements of the defenders.
In 1495, with the death of Ruggerotto, the son of Jacobella and Acclozzamorra, the dynasty of the Berardi became extinct, however already from 1463, Antonio Tedeschini Piccolomini, the nephew of Pope Pio II, had been appointed by the county of Celano, Ferdinando d’Aragona.
Piccolomini brought a huge architectural contribution to the structure of the castle, transforming it into a residential palace even if his interventions were limited to complementaries, additions and decorations.
He, in fact, completed the second floor of the open gallery of the courtyard with rounded arches set up on capitals bearing the symbols of the family: the cross and the crescent moon.
He had several windows opened including the rectangular one of the main facade decorated with lacunar mostra and had many small suspended balconies on the arches which were placed on stone brackets which are still visible on the walls of the building.
More incisive, instead, was the intervention that Antonio Piccolomini carried out on the surrounding walls: he reinforced the corners which were more exposed.. which follows the curves of level, incorporating the old “U-shaped” towers with huge circular towers fortified with a scarp at the lower part. Moreover, to better protect the entrances, he enlarged the walls which corresponded to the entrances which were fortified with antiporta.
The south-east pedestrian entrance was preceded by a triangular rivellino with a circular angled tower.
In 1591 the Piccolomini sold the earldom of Celano to Camilla Peretti, the sister of Pope Sisto V. Today only the first line of inscription over the entrance of the castle which refers to a member of this family, can be read.
In 1647 Celano along with the entire Marsica, was involved in the Neopolitan revolution of Masaniello against the Borboni and the Castle was occupied by the revolutionaries who were supported by the Barone Antonio Quinzi dell’Aquila. After a publication of a revolutionary edict of the Quinzi (8th January 1648), the governor of Abruzzo, Pignatelli, sent the mercenary Pezzola to the Marsica to siege the castle. After numerous unsuccessful attacks, only after the rebellion of Naples, the castle and the city surrendered itself.
After the Peretti the earldom of Celano passed on to the Savelli; also the name of this family appeared in an inscription, now destroyed, placed over the arch of the great staircase which leads to the piano nobile.
Afterwards the earldom passed on to the Sforza-Cesarini and then to the Sforza Cabrera Bovadilla, the last counts of Celano before the abolition of the feuds (1806).
Three quarters of the property of the earldom were administered by the Marquis Claudio Arezzo, and the rest by the Marchesa Giacinta de Torres who was succeeded by the Dragonetti. During the XIX century the walls of the building underwent damage due to the lack of care of the various owners and because of several tremors which provoked the walls to collapse, perhaps not causing serious damage, however they were never repaired by anyone.
The catastrophic earthquake which hit the Marsica on 13th January 1915 and destroyed entire inhabited places, provoked serious damage also to the castle of Celano: many vaults and floors collapsed, the double loggia of the courtyard, a part of the rounds path and some battlements and all the hanging balconies; the angular towers were seriously damaged and the southeast one was half destroyed in its height. The building was completely abandoned for more than 25 years, with serious damage to the structure which already were unsafe.
In 1938 the State expropriated the building for public use and in 1940 it began the restoration which, after the interruption of the second  world war, began again in 1955 and was completed in 1960.
The intervention allowed for a scientific reconstruction of the missing parts based on the abundant photographic documentation which existed. When reintegrating the supporting structure the aseismic norms in Italy were taken into account, using reinforced concrete where necessary.
The castle wall, which at the beginning of the century appeared to be disfigured by additions and super-elevations, was brought back to is simple origins leaving only the elements which had characterized its defensive functionality.
Today there are numerous defensive apparatus such as the covered arrow slits set up along the entire wall and the machicolation which protect the doors.
Inside, under the lee of the defensive wall, remains which were blocked in the ruins of the conservative restoration can be seen; obviously they were premises which were used as stables, cellars and storerooms  for the munitions.
From the south-east side, which is protected by a dry moat, there is an access to the castle trough a double entrance, the first one with a drawbridge, the second one, which is more ancient, with an original arch surmounted by a machicolation.
The wall circumscribes, besides the other green spaces, the… almost in a circular shape which is now used in summer for theatrical performances.
The real building presents itself with the features of a residential building, above all on the piano nobile.
The first two floors do not have many openings, some of which are very small in size; the entrance portal facing southeast is noteworthy. It is characterized by two arches, one with a lower curve and the other circumscribes the lancet arch; the Perrotti holds both the Senese school with a Neopolitan influence of the Durazzesco period.
A string-course cornice, which runs along the entire perimeter of the building, marks the of the impost of the windows of the piano nobile carried out by Lionello Acclozzamorra.
On this floor numerous double lancet ogival windows can be seen, each one different from the other, adorned with capitals and various decors; a splendid triple lancet window which faces northwest and some decorated quadrangular windows carried out by Piccolomini.
The entire construction is surrounded by an ornament which uninterruptedly leans out and is held up by stone brackets with two embosses placed on small brick arches. In the corners of the base rectangular perimeter four battlemented towers about six meters high emerge.
Entering the building one can approach, trough a hall with a barrel vault, the courtyard with a double order archade. The   history of the monument through the years is legible on the architectural structures in the interior of the building. The archades on the ground floor, in fact, reaches the height of the first two floors built by Count Pietro, and it is made up of ogival arches which are still in use in Abruzzo even though it existed at the end of the 14th century.
The above arches of the piano nobile, instead present a double number of spans with rounded arches typical of Renaissance architecture.
The main parts of the building unwind on each side of the rectangular which makes up the plan which is thirty-nine metres  by fifty-one latitude.
In the centre of the courtyard there is the well which made it possible to use rain water gathered in the cistern below.
The interior seems bare since numerous frescoes were lost and of which some 19th century authors have passed on their recollections to us.
There are some doors with stone door frames which outline triangular gables and with architraves placed on capitals decorated with various and bizarre motifs. On the open galley of the piano nobile the portal faces the private chapel of Sant’Andrea with the coat of arms of the Piccolomini carved on the stone architrave.
The connection between the various floors is possible thanks to the great staircase, on the left of the hall of the entrance, and to various internal steps. In the north tower there is a stone spiral staircase which leads to a small security exit.
In correspondence to it, in fact, there is the northwest circular tower of the wall, which has a door which opens to the exterior and is protected by a small trapdoor. This opening was used in case of a siege for the supplies and for the entrance of the reinforcements.  
The castle, given its stately structure and its numerous defense apparatus, << proved to be an impregnable fortress and the lords of the castle hardly ever surrendered themselves..>> .
The building, which was once the centre of the life of the town and of the earldom of Celano, now serves as the hub of the landscape seeing that it is visible for many kilometres from all over the Fucino territory and the surrounding mountains. It emerges considerably due its imposing mass and for its position in respect to the inhabited centre which, in terms of the town planning, has developed in an encircling way around it.