SS. Peter and Paul Counterguard is
a large two-tiered artillery platform, one of the four counterguards designed by the Italian military
engineer Giovanni de Medici in 1640, in order to provide added protection to
Valletta’s land front. This counterguard was built in the form of a stepped
structure, owing to the inclined nature of the terrain. Structurally, the
counterguard is a solid massif with few internal covered spaces, the main
elements of which are vaulted communication passages which link together the
tiered artillery platforms, a 19th-century gunpowder magazine and a WWII
concrete post. It is also linked to a sally-port in the face of SS. Peter and
Paul Bastion directly by means of an arched bridge while a ramp, cut through
the gorge of the counterscarp around 1735, leads down into the main ditch.