One of the most impressive elements
of the land front fortifications of Valletta is its deep rock-hewn ditch. This formidable
defensive feature, on average around 25 m deep, was all carved out of the
bedrock. It was one of the first features of the fortified city to take shape
and also served as a quarry providing most of the stone required for the
building of the ramparts and the houses and palaces of Valletta. In 1649, four
counterguards designed by the Italian military engineer Giovanni de Medici in 1640
were built on top of the counterscarp in order to provide added protection to
the Valletta land front. Around 1735, two pairs of ramps were cut through face
of the counterscarp in order to link these counterguards directly to the ditch.
These galleries were used as civilian shelters during World War Two. The
rock-hewn walls of the counterscarp were also excavated to provide numerous bomb-proof
air-raid shelters for the protection of the civilian population. The ERDF 039
project sought to restore and consolidate the consumed and fissured elements of
the rock-hewn counterscarp walls.