Birgu (, ), also known by its title Città Vittoriosa, is an old fortified city on the south side of the Grand Harbour in Malta. It played a vital role in the Great Siege of Malta in 1565. Its population stood at 2,673 in March 2013. Birgu is a very old locality with its origins reaching back to medieval times. The city occupies a promontory of land with Fort St Angelo at its head and the city of Cospicua at its base. Birgu is ideally situated for safe anchorage, and over time it has developed a very long history with maritime, mercantile and military activities. Prior to the establishment of Valletta as capital and main city of Malta, military powers that wanted to rule the Maltese islands would need to obtain control of Birgu due to its significant position in the Grand Harbour.