Forty years ago, the people of Ulassai, Italy tied their isolated Sardinian village to a nearby mountain. Starting on September 8, 1981, the collective action would last three days, involve almost all of the town’s 1,000 inhabitants, and require nearly 17 miles of light blue denim ribbon.

The ribbon snaked up side streets, draped between balconies, climbed church spires, and finally sailed to the top of Mount Gedili, which towers above the remote, rocky town.