The cave is named after the 'Lenda da Moeda' (Legend of the Coin) involving a 12th-century king.
The temperature remains steady at 18°C (64.4°F) regardless of the external season.
The caves were discovered by chance in 1971 by two hunters.
It is a karst cave system formed within Jurassic limestone layers.
The Natural Science Museum at the site houses findings from the excavations and geological studies of the limestone massif.
Grutas da Moeda, also known as Coin Caves, is a limestone cave system spanning 350 meters in length and reaching a depth of 45 meters below ground. The site is characterized by an extensive collection of stalactites, stalagmites, and flowstones shaped by natural karst processes. The on-site Natural Science Museum displays a permanent collection of fossils and minerals sourced from the region. The cave system was discovered by hunters in 1971 while they were tracking a fox. Its name originates from a local legend regarding a Portuguese king who supposedly dropped a bag of coins there. The interior maintains a constant temperature of approximately 18 degrees Celsius throughout the year. The tourist route is fully accessible via concrete pathways and artificial lighting. Visitors pass through several distinct chambers, including the 'Pastor's Room' and the 'Red Room'.
The 'Pastor's Room' provides the most expansive view of the stalagmite formations.
Wear comfortable, non-slip footwear as the limestone walkways can be damp and slick.
Bring a light sweater or jacket, as the humidity and constant temperature may feel cool after walking in the sun.
Take advantage of the on-site geology museum before or after the tour for context on the cave's formation.
Attempting to touch the stalactites, as skin oils can permanently damage their growth and color.
Touching the rock formations is strictly prohibited to preserve the calcite structures.
