Siena froze in 1348, when the Black Death killed two-thirds of the city and left the cathedral half-built. What survives is a working medieval republic in brick: pilgrim hospitals, tax ledgers painted as art, water tunnels and a conqueror's fortress.
One of Europe's oldest hospitals, taking in Via Francigena pilgrims from the 11th century until 1995. The Pellegrinaio hall keeps Domenico di Bartolo's 1440s frescoes of ward life; the archaeological museum fills the tunnels below.
Built 1316-1325 beneath the cathedral apse to prop up the extended choir. Its hexagonal font (1417-1431) gathers gilded bronze panels by Jacopo della Quercia, Ghiberti and Donatello, whose Feast of Herod brought true perspective to Siena.
Duccio's Maestà of 1311, carried to the high altar by the whole city in procession, hangs here beside Giovanni Pisano's façade statues. A spiral stair climbs onto the Facciatone, the wall of the giant nave abandoned when plague struck in 1348.
The vast brick barn begun in 1226 holds the preserved head of Catherine of Siena and Sodoma's 1526 frescoes of her ecstasy. Downhill, Fontebranda — documented in 1081, vaulted in 1246 — still fills the basin that served the wool dyers.
On the top floor of Palazzo Piccolomini, 105 painted wooden covers that bound the city's tax ledgers from 1258 onward, plus Boccaccio's will and Jacopo della Quercia's contracts. Sienese bureaucracy turned into panel painting.
Headquarters of Monte dei Paschi di Siena, founded in 1472 and the oldest bank still trading anywhere. The square sets the 14th-century Salimbeni palace between the Renaissance Spannocchi and Tantucci wings, around Sallustio Bandini's statue.
Cosimo I raised this star fort in 1561 on the rubble of the Spanish citadel, six years after the Republic of Siena surrendered and its exiles carried the state to Montalcino. The brick ramparts are the monument to a lost independence.
The gate rebuilt in 1604 for Ferdinando I carries the greeting Cor magis tibi Sena pandit — Siena opens her heart to you wider still. Beyond it stands the Antiporto, the outer barbican of 1270 reworked in 1425 to face Florence.
Bernardino preached to crowds in this square through the 1420s. The upper oratory built in his honour holds Sodoma and Beccafumi's Mannerist Life of the Virgin cycle, with gold-ground Sienese panels in the diocesan rooms alongside.
Cosimo I confined Siena's Jews to these lanes in 1571. The synagogue of 1786 hides behind a blank façade in Vicolo delle Scotte, and a plaque in the alley records the community members seized in the deportations of 1943-44.
Twenty-five kilometres of hand-cut aqueduct tunnels, dug from the 1200s, fed the city's fountains. Guided descents follow the gorello channel through sandstone galleries carved by the guerchi, the tunnellers who worked by oil lamp underground.
Behind the unfinished brick façade hangs Coppo di Marcovaldo's Madonna del Bordone of 1261, painted as ransom by a Florentine taken prisoner at Montaperti, along with Pietro Lorenzetti's Massacre of the Innocents.