The Obelisk of Saint Peter is a large ancient Egyptian obelisk located in Vatican City, specifically in Saint Peter's Square. Originally erected in Heliopolis, Egypt, it was brought to Rome by the Emperor Caligula in 37 AD. The obelisk stands about 25.5 meters tall and is made of red granite. In 1586, Pope Sixtus V ordered the obelisk to be moved to its current location in front of Saint Peter's Basilica. It is one of thirteen ancient obelisks still standing in Rome today and serves as a significant historical and architectural landmark, symbolizing the power of the Catholic Church.