The remodelling of Mdina as a Baroque city is primarily due to the foresight of Grandmaster Anton Manoel de Vilhena, who saw the political advantages of extending the patronage of the Order to the Medieval city.

The French engineer Charles François de Mondion was the person responsible for the realization of the Grandmaster's vision in both the military and civil aspects, including a new line of fortification which reflected modern defence concepts. Most of the works were carried out in the course of five years between 1723 and 1728, including the rebuilding of a large part of the walls, the deepening of the ditch, and the shifting of the new main gate to the left of its original site. The defence ditch is found at the front of the city.