The work carried out in 1999-2000, which brought the walls back into view by eliminating the cavities that had accumulated over time, revealed a veritable monumental façade on the surface of the lower part of the G20 tower. The original entrance arch to the tower, accessible by climbing two steps, is flanked by frescoes with a faux-marble architectural decoration, two light yellow half-pillars against a red background. The entrance was monumentalised when the room was reused in modern times, when the tower probably housed a place of worship or prayer that was frequented for a prolonged period of time, as demonstrated by the cross surmounting the entrance to the tower in a drawing of the Military Engineering Institute dated 1883 and various inscriptions with signatures and dates engraved on the frescoes.
