Palazzo delle Papesse

Palazzo delle Papesse in Siena, Italy, is a Florentine-style Renaissance palace erected during the Italian Renaissance in the second half of the 15th century. It was commissioned for Caterina Piccolomini, the sister of Pope Pius II, and from its construction onward it formed part of the Piccolomini family’s urban presence in Siena, connecting local civic life with the influence of a papal kinship.

Work on the building began in 1460 and continued through the later decades of the century, with completion reached around 1495. Finishing touches to the interior followed into the early 16th century; decorative and sculptural elements in the courtyard date to the years after construction and reflect the continuing investment in the house by its owners. During this early period the palace took shape as a Renaissance residence inserted within Siena’s older street plan.

The palace appears in the early modern period in connection with an episode of considerable historical note. From 9 July to December 1633 the scientist Galileo Galilei was given residence there as the guest of the local archbishop, Ascanio II Piccolomini. That accommodation replaced a prison sentence imposed in Rome, and Galileo used the building’s roof terrace for lunar observations during his stay.

At the end of the 17th century the branch of the Piccolomini family that owned the palace died out. A family consortium created to manage Piccolomini interests decided to lease the property to the Tolomei Boarding School, an educational institute founded in 1629 by Celso Tolomei. The Tolomei college occupied the palace until 1820, when it moved to another site, after which the building passed into state ownership and was used for government offices.

The long 19th century brought substantial alteration. In 1864 a restoration was carried out that notably altered grottesque interior decorations, and in 1884 the building entered the ownership of the national central bank, which adapted spaces and introduced neo‑Renaissance decorative schemes on the main floor. Further restorations in the 20th century reshaped interior ornamentation again. Late in the 20th century the palace reopened in 1998 as a municipal center for contemporary art, a function that ceased in 2008. Ownership later changed hands and, following additional work, the building reopened in 2025 to host temporary exhibitions.