The ancient chapel of Palazzo Thun, dedicated to San Biagio, overlooks Via delle Orne no. 1 with a sober and elegant façade: linear pilasters, a semicircular window and a triangular tympanum define its harmonious neoclassical style. The building was designed by the Brescia architect Rodolfo Vantini (1792-1856) as part of the wider architectural renovation of Palazzo Thun, promoted in the fourth decade of the nineteenth century by Count Leopoldo Thun and his son Matteo, the last inhabitant of the palace.
The interior, with a central plan, is dominated by a large circular dome, airy and bright, decorated with faux concentric lacunars painted in tempera. In the plumes appear, in monochrome, the symbols of the four Evangelists — today without the bull of St. Luke — while in the undercarriage of the apse are depicted the mystical Lamb and other Eucharistic motifs. The pictorial decorations of the ceiling were made in 1835 by the Brescia ornamentalist Tommaso Castellini.
Deconsecrated for over a century, the chapel underwent a major restoration in 2006-2007 by the Public Building Service of the Municipality of Trento. The intervention brought to light the original access from Via delle Orne, eliminated the intermediate slab added in the twentieth century and recovered plaster and tempera decorations, restoring the classroom to its original proportions and dignity.
