St. Patrick's Well: The 1537 Well With Two Staircases That Never Meet

In the Italian hilltop town of Orvieto there is a well about 53 metres deep and 13 metres wide, wrapped by two spiral staircases of 248 steps each that never touch. Finished in 1537, St. Patrick's Well let mules walk down one staircase empty and climb the other loaded with water, without ever crossing paths.

The well was born out of panic. In May 1527, troops of Emperor Charles V sacked Rome, and Pope Clement VII escaped to Orvieto, a city perched on a flat-topped block of volcanic tuff with cliffs on every side. The rock made the town hard to attack, but it also made water scarce. If Orvieto were besieged, the pope and the population could die of thirst long before any army climbed the walls.

Clement gave the job to Antonio da Sangallo the Younger, a Florentine architect who also worked on St. Peter's Basilica. Instead of a simple shaft with a rope and bucket, which would have been painfully slow at that depth, Sangallo wrapped the central shaft with two independent helical ramps, one built above the other. Each has its own door on opposite sides of the round building at the top.

The steps are low and wide, designed for pack animals rather than people. According to Umbria's official tourism site, 72 large windows open from the ramps onto the central shaft, letting daylight fall in, though the light fades quickly as you go down. At the bottom, a small bridge crosses the water and joins the two staircases, so a mule could be loaded and turned around without blocking anyone.

Geology made the project possible. A 1983 study in the Journal of the Japanese Association of Groundwater Hydrology describes the layers: soft tuff on top, easy to cut with chisels, and older marine sediments below, where clay traps groundwater in sandy aquifers. Bricks were used to line the shaft. A natural spring keeps the water level steady, and an outlet drains the excess.

The work took a decade. Sangallo was often away, so Giovanni Battista da Cortona supervised the digging and Simone Mosca carved the decorations. Clement VII died in 1534 and never saw it finished. The well was completed under Pope Paul III, whose Farnese lilies still decorate the outside, next to a Latin inscription that roughly means "what nature denied the fortress, human industry supplied".

The famous name came much later. For three centuries it was simply the Well of the Fortress, after the nearby Albornoz castle. In the 19th century, friars of a local convent began calling it after St. Patrick's Purgatory, a cave on an island in Lough Derg, Ireland, that medieval legend described as a gateway to the afterlife. In Italian, "a St. Patrick's well" still means a bottomless supply of money.

Even before it was done, the well was a symbol. Benvenuto Cellini, the great goldsmith, made a medal for Clement VII showing Moses striking a rock to make water flow, with the motto "Ut bibat populus", so that the people may drink, as Orvieto's tourism office recalls.

Today visitors pay a ticket and walk the same 248 steps. In 2022 the well joined the Global Network of Water Museums, an initiative backed by UNESCO's water programme, as ANSA reported.

Sources: Italian Ministry of Culture; Umbria Tourism; Takamura, Journal of the Japanese Association of Groundwater Hydrology (1983); Live Orvieto; Global Network of Water Museums; ANSA (2022); Wikipedia, Pozzo di San Patrizio. Cover: Inside St. Patrick's Well, Davide Papalini, CC BY-SA 3.0.