Originally built in 1540 for Cardinal Girolamo Capodiferro, Galleria Spada was created by Bartolomeo Baronino, of Casale Monferrato, being the architect of the project, while Giulio Mazzoni and a team provided lavish stucco-work inside and out.

In 1632 Cardinal Spada commissioned the baroque architect Francesco Borromini to modify it for him, and it was Borromini who created the masterpiece of forced perspective optical illusion in the arcaded courtyard, in which diminishing rows of columns and a rising floor create the visual illusion of a gallery 37 meters long (it is 8 meters) with a life-sized sculpture at the end of the vista, in daylight beyond: the sculpture is 60 cm high. Borromini was aided in his perspective trick by a mathematician.

The Galleria Spada is a museum in Rome, which is housed in the Palazzo Spada of the same name, located in the Piazza Capo di Ferro. The palazzo is also famous for its façade and for the forced perspective gallery by Francesco Borromini.

The palace accommodates a large art collection, the Galleria Spada. The collection was originally assembled by Cardinal Bernardino Spada in the 17th century, and by his brother Virgilio Spada, and added to by his grandnephew Cardinal Fabrizio Spada.