Trapezoidal light in a pine forest near Pontvallain in 1981

Summary

Near Pontvallain in September 1981, four people observed an intensely bright trapezoidal light inside a pine forest. The phenomenon lasted about ten minutes and vanished abruptly without any sound. Gendarmes arrived shortly after but found nothing. The next day, a circle of flattened ferns was discovered in the same direction, raising suspicions. Later investigation concluded the light was a reflection of the moon through the trees and the ground marks were caused by forestry equipment. Despite these explanations, GEIPAN still classifies the case as unresolved.