Piazza del Campidoglio on the top of Capitoline Hill, took on its current layout in the 16th-century, when Pope Paul III commissioned Michelangelo to complete a renovation for the visit of emperor Charles V of Habsburg to Rome.

The dirt clearing in front, which accommodated the gatherings of the people, was flanked by buildings intended as the headquarters of the Banderesi (the captains of the city militia).

At the height of his fame, Michelangelo was offered the opportunity to build a monumental civic plaza for a major city as well as to reestablish the grandeur of Rome.

From 1534 to 1538 Michelangelo completely redesigned the square, drawing every detail and making the Capitoline no longer turn towards the Roman Forum but towards the St. Peter's Basilica, which represented the new political center of the city.

Today, portions of the temple podium and foundations can be seen behind the Palazzo dei Conservatori, in an exhibition area built in the Caffarelli Garden, and within the Capitoline Museums.

[10] Rossellino built a building with a round arched portico on the ground floor and a façade with cross windows and paired loggias.

The orientation of the pre-existing structures was preserved according to a design principle identical to the one that Rossellino implemented subsequently in the town of Pienza, creating a trapezoidal square.

[11] The 15th-century Palazzo dei Conservatori, at the Capitoline Museums, was almost demolished in 1540 by Michelangelo, but the fifteenth-century design was documented in the drawings by the Dutch painter Maarten van Heemskerck made between 1536 and 1538.

Michelangelo also designed the steep ramp staircase of the Cordonata and the balustrade from which one overlooks the underlying Piazza d'Aracoeli at the base of Capitoline Hill.

It now houses the Roman city hall, after having been converted into a residence by Giovanni Battista Piranesi for the Senator Abbondio Rezzonico in the 18th century.

[6] The steps, beginning at the center of each wing, move gently upward until they reach the inner corner, level off and recede to the main surface of the façade.

In 1587, when the branch of the new aqueduct of the Acqua Felice reached the Campidoglio, Pope Sixtus V announced a public competition for the construction of a fountain on the square.

It was a big project, which was only partially realized with the construction of two tanks leaning against the center of the façade of the Palazzo Senatorio, between the statues of the two rivers and under the niche containing Athena.

The Palazzo Nuovo (English: New Palace) was constructed in 1603 to close off the piazza's symmetry and hide the tower of the Santa Maria in Ara Coeli.

The Cordonata (Italian word, from cordone, which in architecture means "linear element which emphasizes a limit") is a wide-ramped road, gradually ascending from the city to the hilltop.

Benito Mussolini ordered that the paving for the square be completed to Michelangelo's design, done by it:Antonio Muñoz (1884-1960) in 1940, based from a print by Étienne Dupérac.

[16] The geometric paving of the square and the equestrian statue of Marcus Aureliu appear on the reverse of the 50 euro cents minted in Italy, and on all the pages of the Italian passport.