Grotte des Planches

Grotte des Planches is a cave system in Jura limestone with multiple gallery levels and distinct geological features. The formation extends through significant depth with various chamber types and mineral deposits distributed across different sections.

The cave was discovered in 1813 and scientifically explored in 1904, uncovering evidence from the Upper Paleolithic through the Bronze Age. This period of systematic research established its importance as a site with multiple prehistoric occupation layers.

The cave entrance shows traces of prehistoric human settlement, documented through tools and burial sites discovered over time. These archaeological finds reveal how early people used this place as a living space.

The interior remains cool throughout the year and requires appropriate clothing even on warm days. Sturdy footwear is recommended as passages inside are uneven and occasionally slippery.

The lower gallery feeds the Cuisance River, which flows through the cave and represents a rare feature often overlooked by visitors. This underground river contributes to shaping the surrounding landscape and demonstrates the power of flowing water below ground.