Pietra Nairola (Nairola Stone) in Blevio

Pietra Nairola: The Gravity-Defying Giant of Blevio

Perched horizontally on a mountain ledge like a colossal stone table, the Pietra Nairola (Nairola Stone) is one of Lake Como's most impressive geological wonders. To reach this site from Blevio, hikers start in the hamlet of Mezzovico, following an unpaved path toward the Chapel of the Madonna. The boulder is located approximately 600 meters (nearly 2,000 feet) beyond the chapel, situated along the historic mule track that connects Pissarottino di Brunate to Montepiatto.

A Monument of the Ice Age

This massive granite boulder is what geologists call a "trovante" (erratic boulder), a relic of the Quaternary glaciations from approximately 2.5 million years ago. As ancient alpine glaciers moved through the valleys, they transported enormous debris over vast distances; when the ice finally melted, these giants were left stranded on the mountainsides. The Pietra Nairola is particularly famous for its sheer scale:

Length: 7.5 meters (approx. 24.6 feet).
Width: 4 meters (approx. 13 feet).
Height: 4.5 meters (approx. 14.7 feet).

The first to scientifically study these phenomena was the renowned geologist Antonio Stoppani (1824–1891), who identified that these granite and serpentine boulders were foreign to the local limestone landscape.

Devils, Miracles, and Folklore

Local legends add a layer of mystery to the stone’s scientific origin. One ancient tale speaks of a second, now-destroyed boulder nearby; it was said that devils used the two stones as platforms to hurl fireballs at one another. A later Christian legend attributes the boulder's precarious position to the Madonna, who supposedly used her veil to stop the stone from sliding off the ledge.

Preserving a Natural Treasure

In recognition of its scientific and cultural importance, the Pietra Nairola was declared a National Monument by the Lombardy Region in 1984. Today, it is protected by the Larian Triangle Consortium. When visiting, hikers are encouraged to exercise caution on the trails and show the utmost respect for this ancient natural heritage.