The Museo delle Grigne presents a natural history collection (fossils, minerals and a butterfly collection housed in the adjacent Villa Clotilde), archaeological finds, tools used by the inhabitants of Esino up to the early 1900s, and evidence of the village's more recent history — including a renowned tapestry school and Wikimania, the international congress of Wikipedia contributors held here in 2016.
In the historic center of Esino Lario, just steps from the main square, sits one of the most fascinating paleontological museums in the Lombard Prealps. The museum holds fossil specimens found in the limestone rocks of the Grigna Settentrionale — rocks deposited on a shallow tropical seabed 240 million years ago, in the Middle Triassic.
The Grigna mountains are an open stone book about the prehistory of life on Earth. The same limestone walls climbed by alpinists today were once seabeds inhabited by giant reptiles, ammonites and primitive fish. This museum tells that story — with original fossils, scientific panels and displays accessible to children.
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The most celebrated specimen
Besanosaurus leptorhynchus
Middle Triassic Ichthyosaur · Besano Formation
One of the largest marine reptiles ever found in Italy: up to 8 metres long, living 240 million years ago in what is now the territory between Esino Lario and Besano (VA). The Besanosaurus is considered one of the most complete and scientifically important ichthyosaurs in Europe — and Esino Lario is one of the sites where its remains were found.
The museum collections
Marine invertebrates
Ammonites & cephalopods
Ammonites are the most common fossils in the Grigna limestone rocks. Spiral-shelled creatures similar to modern nautiluses, remarkably diverse in form. Some specimens display the external shell with its characteristic fractal suture visible to the naked eye. Pictured: Lumachella a Trachyceras, one of the most significant specimens in the collection (EL100).
🕐 240 million years ago · Middle Triassic
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Marine reptiles
Ichthyosaurs & nothosaurs
Triassic marine reptiles were the apex predators of the ecosystem. The museum holds bone fragments and impressions of ichthyosaurs (similar to modern dolphins) and nothosaurs found in the local rocks. The Besanosaurus — the most celebrated specimen — is the giant of this collection.
🕐 240–230 million years ago
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Primitive fish
Triassic actinopterygians
Ossified Triassic fish, among the earliest ancestors of modern fish. Specimens from the Besano Formation (bituminous layers present in the Esino territory) show scales and bones preserved in minute detail thanks to the chemical nature of the sediment.
🕐 240 million years ago
Local geology
Rocks & minerals of the Grigna
A section dedicated to the geology of the Grigna: tropical platform limestones, dolomites, bituminous formations. Samples collected from the various geological formations of the area with an explanation of the tectonic history — from the Tethys Sea to the Alpine uplift. The collection also includes minerals and the natural history collection of Villa Clotilde.
🪨 From 240 Ma to today
The museum's home
Villa Clotilde
The new home of the Museo delle Grigne is housed in the historic Villa Clotilde, within the municipal park of Esino Lario. The villa hosts the museum's butterfly collection alongside the exhibition spaces of the main building dedicated to fossils, minerals and archaeological finds.
The villa's park is an important green space in the village and forms the ideal natural backdrop for a collection that tells the story of the area's biodiversity — from butterflies to Triassic ammonites, from 19th-century rural life to internationally significant events such as Wikimania 2016, the global congress of Wikipedia contributors hosted in Esino Lario.
Scientific context
240 million years in a rock
The Grigna limestone preserves one of the most complete Triassic sequences in Europe. Here is what the rocks tell us:
Middle Triassic (Ladinian)
A shallow tropical sea — the Tethys — covers what is now northern Italy. Coral reefs, muddy seabeds, giant predators. The bituminous rocks of the Besano Formation trap intact organisms for millions of years.
~242–237 million years ago
Upper Triassic
The carbonate platform consolidates. Deposits of dolomites and massive limestones. The environment becomes more energetic — algal reefs, oolites, bioclastites. These are the rocks that form the walls of the Grigna today.
~237–201 million years ago
Alpine Orogeny
The collision of the European and African plates lifts the marine sediments to form the Alps and Prealps. The Triassic seafloor rocks are raised to over 2,000m altitude — becoming the limestone ridges of the Grigna we see today.
~65–2 million years ago
Today
Triassic fossils emerge on the walls and scree slopes of the Grigna, exposed by glacial erosion and hiking. Many of the Museo delle Grigne's specimens were found by local hikers and donated to the museum during the 20th century.
Present
Cultural itinerary
The Prestigious Villas of Esino Lario
From the late 19th century, Esino Lario became a holiday destination for wealthy Milanese families, earning the nickname "La Perla delle Grigne" (The Pearl of the Grigna). Many villas were built by the wealthier visitors, creating a unique Liberty and Rationalist architectural heritage in this alpine setting.
🏛️ Villa Clotilde
Built by the Cazzaniga family. Today it is Esino Lario's cultural center: it houses the Pietro Pensa archives, the library, the tourist office and the Ecomuseo delle Grigne. The museum (from 2016) is in its park.
🏛️ Villa Gilera (1930s)
Built by Giuseppe Gilera, founder of the famous motorcycle manufacturer. A piece of Italian industrial history on Lake Como.
🏛️ Villa Gilardi (Hotel Rosa delle Alpi)
Built in the 1930s by the Gilardi family, now home to the Hotel and Restaurant Rosa delle Alpi. The same property includes Hotel La Montanina, originally a silk-winding mill.
🏛️ Villa Minuccia & Villaggio Riva
Villa Minuccia designed by architect Mino Fiocchi for sculptor Michele Vedani. Villaggio Riva: 12 villas with gardens built between 1936 and 1942.
📍 The Prestigious Villas walking itinerary takes about 1 hour. Map and guide available at the Tourist Office in Villa Clotilde.
Frequently asked questions
Everything you need to know
Is admission to the Museo delle Grigne free?
Yes, admission is free. The museum is managed by the Municipality of Esino Lario and open to the public at no charge. Donations for the upkeep of the collections are welcome.
Is the Museo delle Grigne worth visiting?
Absolutely, especially if you have hiked on the Grigna or are interested in geology and paleontology. The fossils are genuine originals — not casts — and include some remarkable specimens from the Triassic sea that covered this area 240 million years ago. The museum is small (1–1.5 hours is enough) but the quality of the exhibits is genuinely impressive for a village museum. Free admission makes it an easy addition to any visit.
Is the museum suitable for children?
Yes, suitable for children aged 6 and over. The giant marine reptiles and ammonite fossils are very popular with children. The museum also offers educational activities on request for school groups. A visit takes about 1–1.5 hours for families with children.
How do I get to the Museo delle Grigne?
The museum is in the center of Esino Lario at Via Roma 2, 2 minutes on foot from the bus stop (SP62 bus from Varenna, 30 min). By car: SS36 toward Lecco/Colico, exit Varenna, then SP62 to Esino Lario (12km). Free parking in the village.
Can you find fossils on the Grigna?
Yes — the Grigna rocks do contain fossils, especially in the limestone zones between 1,500 and 2,000m. However, fossil collection is regulated within the Grigna Settentrionale Regional Park. Collecting or removing fossils is prohibited. If you find something interesting, report it to the Museo delle Grigne — many of the displayed specimens were donated by hikers.