Mdina, also known by its Italian-language titles Città Vecchia ("Old City") and Città Notabile ("Notable City"), is a fortified city in the Northern Region of Malta which served as the island's capital from antiquity to the medieval period. The city was founded as Maleth around the 8th century BC by Phoenician settlers and was later renamed Melite by the Romans. Ancient Melite was larger than present-day Mdina, and it was reduced to its present size during the Byzantine or Arab occupation of Malta. During the latter period, the city adopted its present name, which derives from the Arabic word 'Medina'. The city remained the capital of Malta throughout the Middle Ages, until the arrival of the Order of St. John in 1530.

Valletta is not the first capital city of Malta, nor the second. Many people are aware that Mdina was the first capital city of Malta. Vittoriosa was the de facto capital city of Malta from 1530 to 1571. the capital city until 18th March 1571. On this day, Valletta became the capital city. Today, Mdina is one of Malta's major tourist attractions, hosting about 750,000 tourists a year. No cars (other than a limited number of residents, emergency vehicles, wedding cars, and horses) are allowed in Mdina, partly why it has earned the nickname the 'Silent City'.

More Info: en.wikipedia.org