Bronze medal of Pius IV, by Gianfederico Bonzagna

Pius IV was pope between 1559 and 1565, and the Porta Pia was among his civic improvements to Rome. Situated at the end of a new street, the Via Pia, it was designed by Michelangelo. Construction began in 1561 and ended in 1565, after the artist's death. This medal by Gianfederico Bonzagna shows an early plan by Michelangelo, very different from his final design.

Pius was a great admirer of Michelangelo and restored his salary as architect to St Peter's, which had lapsed under his predecessor Paul IV.

Principally because of his work for the popes, Michelangelo's income and savings dwarfed those of celebrated contemporaries such as Titian. When he died in 1564, his estate was worth more than 24,000 florins, an incredible sum for an artist. He always wanted access to ready money, and among the few possessions near his bedside at his death was a chest of 8289 gold ducats and scudi, amounting to almost 30 kilograms of gold.