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Monte Porzio Catone and Astronomical Observatory, looking at the stars

Monte Porzio Catone, very close to Rome, which is admired from here in splendid views, combines the charm of the past with the wonder of the starry sky. Lying on a hilly relief born from a volcanic cone of the Latium Volcano, it stands predominantly on the southeastern outskirts of Rome.

This location favored the construction of the Astronomical Observatory here. The territory, at first gently hilly, turns into real mountains; heights rich in chestnut groves planted in the 18th century, replacing the ancient oak forests.

A green oasis in the Castelli Romani Regional Park

The ancient village, perched on top of a tufa block, dominates the surrounding landscape, while the land slopes down to the plain on one side and up toward the Tusculum on the other.

Part of this natural beauty is protected by the Regional Park of the Castelli Romani, a green oasis that holds valuable flora and fauna. A natural corner on Earth to admire the beauty of the stars not only from the Astronomical Observatory but also with the naked eye on clear nights.

A leap through history from antiquity to the Renaissance

Like other villages in the Castelli Romani, Monte Porzio Catone has its roots in the flight of the inhabitants of ancient Tuscolo, destroyed by the Romans in 1191. The first official mention dates back to the 11th century, when Gregory III ceded the church of Sant’Antonino in “Monte Porculo” to the Benedictines. That name, a probable corruption of “Mons Porcii,” would derive from the Porcia gens of the Catoni, who owned a villa here.

Other historical references are found in a papal bull of 1074, in which “Monte Porculi” appears as the property of the monastery of St. Paul Outside the Walls. In the 15th century, the castle passed to Teodobaldo degli Annibaldi to support Pope Boniface IX against Niccolò Colonna.

The urban development of Monte Porzio Catone began only in the 16th century thanks to Cardinal Marco Sitico Altemps. And it continued in the 17th century with the cession to the Borghese family, who built their palace and rebuilt the church of St. Gregory the Great.

The city that changed the world’s time

In the most famous of the Renaissance Tuscolan villas, Villa Mondragone, Gregory XIII with the bull “Inter gravissimas” of February 24, 1582 introduced a new calendar. Which, based on the 1543 measurements made by the astronomer Nicholas Copernicus, replaced the Julian Calendar then in force. The Gregorian Calendar, still the most widely used in the world today, overcame the date mismatch with its predecessor by erasing ten days from October 4 to 15, 1582.

Resuming the history of the village, in 1581 this passed to the Altemps. In 1613 it was purchased by Cardinal Scipione Borghese. As mentioned, in 1666 Prince Giovan Battista Borghese, lord of the lands of Monte Porzio, rebuilt the church dedicated to St. Gregory the Great. Also with the intention of making it a center of reference to fortify the local faith.

In 1849 there were 1180 inhabitants here; today there are about 8500 residents. In 1872 “Cato” was added to the name to distinguish it from Monte Porzio in the Marche region.

Looking up, discovering the stars

But the real gem of Monte Porzio Catone is undoubtedly the Astronomical Observatory, an imposing rationalist building erected on the remains of a Roman villa. That of Matidia Augusta, a close relative of Emperor Hadrian in the first century AD. Terraces of the villa are still visible.

The Observatory was planned in 1939 after Hitler donated an equatorial Schmidt telescope to Mussolini. It was built starting that year and finished only in 1965 because of damage caused by the world conflict.

A branch of the National Astronomical Observatory of Rome, it houses a fascinating Observatory Museum and has a long tradition of scientific research and astronomical outreach.

Research activities cover INAF’s five main thematic areas: Galaxies and Cosmology, Stars and Interstellar Medium, Solar System, Relativistic Astrophysics, and Technology.

As well as important infrastructures dedicated to science popularization: the AstroLAB (Interactive Astronomy Laboratory open to the public and school visits) and the Monte Porzio Telescope (MPT). The environments of the Observatory preserve period atmospheres such that they have been used as movie sets for historical films such as “The Boys of Via Panisperna.”

Between history and science, the small town of Monte Porzio Catone thus boasts an international reputation. A reputation that makes it a center of tourist interest associated with visiting all the Castelli Romani.

With the Blog of Rome and Latium Region, Around Rome guides you to discover the territories for the pleasure of satisfying curiosity and putting culture at the service of people and businesses

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Edited by il NETWORK | text Andrea Franchiniphoto Ezio Bocci

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