Floriana is a suburb of Valletta and shares with it the impressive harbour fortifications. It also lies within the capital's landward fortifications which reach as far as the Portes des Bombes on the main Valletta approach road. Floriana is named after the 17th century military engineer Pietro Floriani who was commissioned by the Knights in 1636 to extend Valletta's fortifications. Floriana was conceived as an entire fortress city in front of Valletta. The town is characterised by open spaces, gardens and some fine patricians' houses. Highlights include the elegant St Publius Church, overlooking Granaries Square and the Argotti Gardens on St Philip's Bastion. The vast flag-stoned Granaries Square hides a number of deep silos which were built in the late 17th century to ensure food supplies for Valletta in times of war. Also of interest is the Mall; today a garden but once an area where the Knights played a kind of tennis. This narrow strip of greenery is dotted with statues and plaques commemorating events and personalities of Maltese 20th century history.