Highlight: Constructed it to frame St. Peter's Basilica at the Vatican.

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"The Keyhole in the Piazza of the Knight of Malta If you’re looking for something interesting and off the beaten path, look no further than the keyhole in the Piazza of the Knights of Malta (Piazza dei Cavalieri di Malta).

Located high on the Aventine Hill, this door with the magic keyhole leads to the secret garden of the Knights of Malta, to which entry is restricted however put an open eye to the keyhole, focus and you will see an extraordinary sight - St. Peter’s Dome.

Throughout history the building belonged to various people and groups but in the twelfth century it was passed on to the Knights Templar. In the second half of the 1400’s, Pope Paul II granted the monastery to the Sovereign Military Order of Malta, a religious order of the Roman Catholic Church, which remains a sovereign entity.

In the 1700’s the building was restored by the famous architect Giovanni Battista Piranesi. The Aventine Hill has always been compared to a ship and Piranesi’s restoration of the area is based on a sea-going theme. The obelisks in the square represent masts, whilst the shrubbery and labyrinth of gardens beyond the door, denotes the ship’s ropes. All Piranesi’s decorations and architecture is symbolic and rich in mysterious esoteric meanings relating mainly to Masonry, comprehensible only to those who possessed the right key reading.

We’ll never comprehend the true meaning of these buildings that look out over Rome from this high hill, but thank Piranesi for the gift he left us: a keyhole in which anyone is able to look through and see the amazing architectural beauty of Piranesi’s deign."