Piazza Carlo Alberto, Historical square in central Turin, Italy

Piazza Carlo Alberto is a pedestrian square behind Palazzo Carignano, bounded by Via Cesare Battisti, Via Principe Amedeo and Via Carlo Alberto. It occupies the former inner garden of Guarini's Baroque palace, whose 19th-century rear facade faces the square. At its centre stands Carlo Marochetti's equestrian statue of King Carlo Alberto, unveiled in 1861, with four allegorical female figures and four soldiers of the Royal Sardinian Army around the base.

The square emerged between 1842 and 1859 when defensive walls were demolished to create this public space. Its naming after King Carlo Alberto honors Piedmont's role during the wars of Italian unification in that era.

The name honours Carlo Alberto of Savoy, king of Sardinia from 1831 to 1849, whose family owned Palazzo Carignano. The equestrian statue by Carlo Marochetti, inaugurated on 21 July 1861, shows him with his back to the library and a raised sword; at its base stand four allegorical female figures (martyrdom, liberty, civil equality and the Statute) and four soldiers of the Royal Sardinian Army, with reliefs of Goito, Santa Lucia, his abdication and his death at Oporto.

The square has been fully pedestrianized since 2006, after lengthy debate, so it is reached on foot from Via Po, Via Giuseppe Verdi and Via Carlo Alberto. A stop on metro line 2 is planned for the future. The equestrian statue faces the 19th-century entrance of Palazzo Carignano, with its back to the library.

Friedrich Nietzsche lodged on the third floor of the corner building between the square and Via Carlo Alberto, toward Via Po, in 1888 and 1889. There he wrote The Antichrist, Twilight of the Idols and Ecce Homo. A plaque placed by the city council in October 1944 marks the stay.