The name refers to the military functions that it held in the past. Municipality in the province of Padua, located between the rivers Brenta and Musine, Cittadella is characterized by an extremely original appearance, enclosed in a ring of fortified walls that extends for 1460 meters, interrupted only by watchtowers and four gate entrances, surrounded in turn by a wide moat and a row of trees. Inside, the streets are developed along two perpendicular lines, according to the Roman Castrum design.
The town was founded in 1220, by the Lords of Padua, based on a project of the military engineer Da Cartura. The particularity of the design is the town's form: a polygon with an irregular ellipse, that created a sort of disagreement with those who wanted the fortified cities to be rectangular or square. The location was chosen for its strategic position between the two rivers and was a perfect outpost to counter against the rival city of Treviso, less powerful, that about twenty years earlier, had founded a fortified center, with similar purposes, in Castelfranco Veneto. Padova granted the inhabitants of Cittadella with its own statutes, a self-government and the jurisdiction over a vast territory. In the XIII century it submitted the dominion of Ezzelino Romano, passing to the Carrara at first, and to the Della Scala, then. Re-assigned for a short period to the Carrarresi, in the XV century the town was conquered by Venice, who turned the centre from a military garrison into an important trading outpost.
- the Cathedral, built between the XVIII and XIX centuries on a project of the architects, Cerato, Barera and Berotti, features a single nave plan with six altars and enriched by works by important artists, including: "the Supper at Emmaus", depicted by Jacopo da Ponte in XVI century, a masterpiece of the artist Bastiani and a painting by Palma the Younger. The neo-Classical façade was completed in 1913;
- the Parish Church of San Donato, located outside the city walls and built between the IX and X centuries, features a very simple façade and consists of three naves separated by arches and decorated with frescoes. It represented for several centuries the most important religious center of the area;
- the Church of Torresino, named so due to its location near to Porta Padua, was built in the XIII century on the remains of a pre-existing building;
- the ancient Parish Church of Saints Prosdocimo and Donato, built in the XIII century and rebuilt in the XIV;
- the late XV century Convent of San Francesco;
- the Tower of Malta, located next to Porta Padua, which was built in 1251 by Ezzelino Romano and was used as a prison for the nobles of Padua;
- the almost perfectly preserved city walls and the four fortified gates, including Porta Padua and Porta Bassano;
- the Social Theatre, built in the XIX century by Giacomo Bauta, features a neo-Classical façade realized by the artist Jappelli;
- the XIV century Palazzo del Podesta, in Gothic style;
- Palazzo Mantegna