How San Gimignano was built and evolved over time

San Gimignano is a vertical town inside a very small wall, and both facts are deliberate.

The towers

A medieval tower-house is a single structure doing three jobs: a fortified residence, a strongroom for goods and money, and a public claim to rank. They are built of local stone and brick on small footprints, which is why they go up rather than out — the plots inside the walls were narrow and the competition was for height.

At the end of the Middle Ages there were seventy-two. Fourteen survive. The others came down over the centuries through collapse, demolition and absorption into later buildings, and a careful walk will show you truncated towers built into house fronts along both main streets. The Torre Grossa, reached through the Palazzo Comunale, is the only one open to climb, and climbing it is the only way to understand the group as a group.

The squares

Piazza della Cisterna is the better piece of urban design and the harder one to photograph: triangular, sloping, with the paving partly 13th-century, named for the cistern of 1287 and holding a well of 1346. A medieval town's water supply was its most valuable public asset, which is why the finest square in San Gimignano is built around a cistern rather than a church. Piazza del Duomo opens off it at a higher level, with the Collegiata's steps on one side.

The walls and the scale

The inscribed area is 13.88 hectares. That is the whole historic town — smaller than many single city parks — and it explains why San Gimignano feels dense rather than grand. Everything had to fit inside the circuit, so the streets are narrow, the buildings are tall and the squares are the only open ground.

Why it survives

Not through care. The 1348 plague halved the population and the town submitted to Florence shortly after; from then on it was a minor hill town in someone else's state. Nobody built a Renaissance palace over a medieval tower here because nobody could afford to.