The area has been inhabited since the Bronze Age, and the site now occupied by the Cittadella is believed to have been the acropolis of the Punic-Roman city of Gaulos or Glauconis Civitas.

The new fortifications were criticized in later decades, and plans to demolish the entire citadel were made multiple times in the 17th and 18th centuries, but were never carried out.

The Cittadella briefly saw action during the French invasion and subsequent uprising in 1798; in both cases the fortress surrendered without much of a fight.

Although there is only limited evidence of Neolithic remains in the Cittadella or Victoria, it is likely that the area has been inhabited since the Stone Age, given its size and strategic position.

Archaeological remains such as pottery show that the site of the Cittadella was definitely inhabited during the Bronze Age, in the Tarxien Cemetery and Borġ in-Nadur phases of Maltese prehistory.

Bronze Age silos were discovered outside the Cittadella in the 19th century, suggesting that during this period the settlement was larger than the present-day citadel.

The city consisted of an acropolis on the site of the Cittadella, and a fortified town in an area now occupied by part of Victoria.

In 1969, traces of massive walls were discovered during building works in Main Gate Street (Maltese: Triq Putirjal), to the south of the Cittadella.

At this point, one-third of Gozo's population lived in or around the Cittadella, and the island's inhabitants were required to spend the night within the citadel.

By the end of the 13th century, the Cittadella housed noblemen from Sicily and mainland Italy who represented the Count of Malta.

[8] Over time, the Cittadella became too small for the growing population, and by the 15th century the suburb of Rabat began to develop on the site of the Roman town.

Governor Galatian de Sesse offered terms of surrender, but they were refused, and the castle fell within a matter of days.

[18] The castle remained the only fortified refuge against attack for the island's inhabitants until Fort Chambray was built in the mid-18th century.

[20] The engineer Antonio Maurizio Valperga suggested to rebuild the wall around the suburb and further strengthen the Cittadella, but there were no funds for this proposal.

[21] By the early 18th century the Cittadella had assumed the role of a fortress, with a significant proportion of its houses falling into ruin or being in a poor state.

An attack on Gozo took place in 1708, and, in 1715, the engineer Louis François d'Aubigné de Tigné made the same suggestions as Valperga, but a lack of funds prevented any work from being carried out.

Troops led by Jean Reynier landed near Ramla in the early afternoon, and part of the 95th Demi-Brigade marched to the Cittadella.

[22] The invasion was followed by a French military occupation, but within three months discontent among the population led to revolt on the main island of Malta.

A day later, the British transferred control of the Cittadella to the Gozitans, who set up a provisional government led by Saverio Cassar and briefly administered the island as the independent state La Nazione Gozitana.

[32] The 19th-century reservoir in the ditch was also converted into the Cittadella Visitors' Centre, with this project being entrusted to Martin Xuereb & Associates[34] and Sarner International.

A small structure consisting of two sets of stones in circular arrangements was discovered in Cathedral Square in December 2014.

These include a ramp with a drawbridge which served as the original entrance to the fortress, and a sally port within a flank of St. Michael's Bastion.

This location was originally chosen because it is a naturally defensible hill, dominating the surrounding countryside and having views of large parts of the coastline.

The fortifications of the Cittadella consist of a semi-circular enceinte in the northern end of the city, and bastions linked together with curtain walls in the south.

[57] The southern perimeter of the Cittadella is surrounded by a ditch, which originally extended from St. Martin's Demi-Bastion to the Low Battery but now begins at St. Michael's Bastion due to 19th-century alterations.

[13] A small triangular ravelin stands near the entrance to the city, but this has lost most of its original stonework and has been converted into a garden, losing its legibility as part of the fortress in the process.

The Chapel of St. Joseph, known as ta' fuq is-sur ("on the bastions"), was originally built in around the 11th century, and it was dedicated to Nicholas of Bari.

The site was given to the Confraternity of St. Barbara in 1598, who built the existing chapel in the early 17th century, during the magistracy of Alof de Wignacourt and around the same time when the fortifications were being reconstructed.