The first square of modern Rome created by the criteria of a uniform project due to the genius of Michelangelo, rises on the Capitol hill (Capitolium), the place where an old village had been and the appointed place to dedicate numerous temples to the Roman deities. 

In 1536, during the visit of the emperor of Spain Charles V, Piazza del Campidoglio underwent a series of changes due to the state of neglect of the hill. Michelangelo was commissioned by Pope Paul III to lay out the square. The Florentine architect realized an elegant base for the equestrian statue of Marcus Aurelius, placed in the middle of the hill in 1537 and it became the centre of the new town scheme. 

In addition, Michelangelo designed the imposing “Cordonata”, a ramp of wide shallow stairs, that allowed an easy climb to riders, culminating with the solemn balustrade, with classic marble groups here placed in following decades. Around 1546 Michelangelo realized the façade of the Palazzo Senatorio (backdrop of the main view) with a double staircase framing the wonderful fountain. 

He restored the Palazzo dei Conservatori and began to build a second palace, the Palazzo Nuovo – today the seat of the first public museum in the world inaugurated in 1734 , the Musei Capitolini – placed opposite the first to mark out the three sides of the square. The Palazzo Senatorio was completed after Michelangelo’s dead by Giacomo della Porta, and the second by Carlo Rainaldi. 

The works were completed in 1655. Notwithstanding the long period of time passed and the presence of different architects, Piazza del Campidoglio has today a wonderful stylistic unity.