Beyond the Portal of the Zodiac is the last ramp to the church: it is a solemn green stone staircase, under the yoke of four impressive flying buttresses designed by Alfredo D'Andrade and completed in 1937. At the end of the nineteenth century, this area was covered over with buildings and therefore the Portal of the Zodiac did not give access to an open terrace, but to various rooms through which you came to the church. D'Andrade decided to demolish these rooms and plan the staircase and the flying buttresses to give direct access to the bare south wall of the church.
The wide terrace offers a good view of the ornate Romanesque portal in gray and green stone that leads to the church. It was built by the architects of Ugone in the early XIth. Century. It is most elegant, rounded and wide; and it still exudes a strong air of welcome, security, calm. The arches, formed of arris and stringcourse, are supported by half-columns with floral capitals.
It is surmounted by a dripstone which ends on the right with the head of a hooded monk, and on the left with that of a boy (now missing) . The half-columns, which have Gothic trefoil arches, added later, are the remains of the porch that protected the portal.
The doors of walnut, made in 1826, show the weapons of St. Michael the Archangel and the devil in the shape of a snake with a human face.
On the left top of the portal is inserted the Roman tombstone of Surio Clemente dated first century A.D.; clear evidence of the presence on this mountain of a Roman garrison.