The Obelisks were regarded by the ancient Egyptians as the symbols of the sun god ‘Ra’ and were installed in pairs at the entrance to their temples. Of the numerous obelisks that once graced the temples of ancient Egypt and proclaimed the greatness of the Pharaohs, only 28 still stands today and out of that number only six obelisks are still standing in Egypt, the country of their origin. The rest were plundered and transported to different locations and are now scattered around different cities of Europe. Rome alone hosts 13 Egyptian obelisks, which were brought to Rome by various Roman Emperors. Among all of them, the Vatican Obelisk, also known as the Caligula’s Obelisk is located in St. Peter's Square and is the only ancient Egyptian obelisk that has remained standing in the city since Roman times.

St. Peter's Square is a large plaza located directly in front of St. Peter’s Basilica in the Vatican City. The square and the basilica, both are named after Saint Peter, an apostle of Jesus and the first Catholic Pope. At the center of the square stands a non-inscribed Egyptian obelisk of red granite, hewn from a single block of granite and stands 25.31 m high on a base that is 8.25 m wide. The obelisk was originally installed in Heliopolis, Egypt. But, as there are no hieroglyphs on it, it is not known which Pharaoh ordered the construction of the obelisk. It is assumed that the obelisk was erected at Heliopolis around 2500 BC, while others opined, it was built by the Pharaoh Mencares in 1835 BC in honor of the Sun God.

Nevertheless, the obelisk was moved to the Julian Forum of Alexandria by the Roman Emperor Augustus, where it stood until AD 37, when the infamous Roman emperor Gaius Caligula ordered the demolition of the forum. It was Caligula, who brought the obelisk to Rome in 37 AD. With a height of 25.5 m and weighing an estimated 326 tons, it was the largest non-inscribed obelisk to leave Egypt. A ship was specially built to transport it from Egypt, which was later sunk to make the foundation of one of the breakwaters of the Claudian port at Portus Augusti and a lighthouse built on it.

In Rome the obelisk was originally installed in the gardens which Caligula had inherited from his mother. Later, it was shifted on the central spina of Caligula’s circus, a chariot racing stadium and mass entertainment venue, which was started by Caligula and completed during Nero’s reign. During the reign of Nero, it would be renamed the Circus of Nero and the arena would witness Nero's countless brutal games and ruthless Christian executions.

With time, the Circus of Nero fell into abandonment, but the obelisk remained there for 1.500 years and in 1586 Pope Sixtus V decided to have the obelisk moved to its present location, in front of the construction site of the new St. Peter Basilica, in the Vatican City, west of the River Tiber. Finally, it was moved and installed safely by engineer and architect Domenico Fontana, with the help of over 900 men and 140 horses. It took more than 5 months to move the obelisk and pull it upright. The job was perfectly done, as the obelisk still stands in its place. In fact, the Vatican Obelisk is the only Egyptian obelisk in Rome that has not toppled since ancient Roman times.

During the middle Ages, it was believed that the gilt ball on top of the obelisk contains the ashes of Julius Caesar. However, when the ancient metal ball was removed during the relocation process, it was found empty. At present the ball is in a Rome museum, Museo dei Conservatori.

After the obelisk was moved and before the cross was placed on top, he conducted the ancient rite of exorcism against the obelisk. The text of the exorcism is carved in Latin into the western and eastern sides of the base of the obelisk. The Pope replaced the ball with a cross, which is said to have certain relics of Jesus Christ.

The Vatican obelisk is giant Sundial and can accurately indicate the midday. The base of the obelisk is adorned with three different coats-of-arms or family emblems. The four lions refer to Pope Sixtus V. The bronze eagles, added only in 1713 indicate the Conti family of Pope Innocence XIII, while the hills and stars belong to Pope Alexander VII‘s Chigi family.

The huge monolith Vatican obelisk, standing at the centre of Piazza San Pietro or St. Peter’s Square, is perhaps a symbolic expression of the conquering power of the Church.