This column, dedicated to the immaculate conception of the Virgin Mary, was installed in Piazza di Spagna in 1854. Unlike the Christian Church, Catholics firmly believe that the Virgin Mary, too, was conceived without sin.

The monument was created by Luigi Poletti. In making the memorial, he used several types of marble. The column itself was brought from a Benedictine monastery near the Campus Martius in 1777. Its height is 11 m.

The pedestal is also marble, and on it are installed the figures of the biblical prophets Moses, Isaiah, Ezekiel, and the great King David. They are not only an ornament of the column, but also serve as additional supports for it.

And at the top of the monument there is a statue of the Virgin Mary. She stands on a globe and a crescent moon – symbols of the summit of the world. Under her feet is a serpent, which since ancient times has been associated with original sin, but here it is defeated.

There is always a wreath of flowers hanging on the statue's right hand. Moreover, it is neither bronze nor plastic, but completely real. Every year, on 8 December, the Pope comes to this square with a wreath of fresh flowers. As a rule, these are white lilies – a symbol of purity. With the help of a crane, these flowers are placed on the hand of the Virgin Mary, and they hang there for a whole year – right up until the next ceremony.