Poised on the edge of an Italian cliff, the Pozzo di San Patrizio is an astounding, windowed well that was built to store up war water.

Located in the city of Orvieto, the well was built in the early 1500s at the behest of then Pope Clement VII. The Pope had sought refuge in the city as Rome was being sacked and was concerned that there was not enough water for the area should the city fall under siege. St. Patrick's Well, as the site is known in English, was thus commissioned. Reaching over 170 feet into the ground with a 43-foot diameter, the well's shaft was built with 70 windows that open onto a set of dual staircases which wrap around the center in a double helix pattern. These two staircases allowed for pack animals to travel up and down the well simultaneously without having to run into one another. The well took almost ten years to complete, and by the time diggers finally struck water, Pope Clement had passed away, rendering the purpose of the dig obsolete.       

Today the well is still in much the same condition as when it was built and visitors can still take the long winding steps down to the bottom like the mules of yore. Pozzo di San Patrizio's unique construction and impressive depth are a terrific reminder that war can often inspire innovation.