Faial’s Caldeira: the Sleeping Crater at the Heart of the Blue Island

At the heart of Faial lies a vast hollow: a crater nearly 400 metres deep, blanketed in damp vegetation and shrouded in mist for much of the year. Locals simply call it the Caldeira.

The crater of the island’s largest volcano

With a diameter of about 2 km and a depth of 400 metres, the Caldeira is the result of repeated collapses of a volcanic edifice more than 400,000 years old, whose last eruption occurred roughly 1,000 years ago, blanketing much of the island in incandescent pumice. At the bottom lies a wetland with intermittent lakes and a trachytic dome known as Rocha do Altar.

A nature reserve known as the “Cathedral of Silence”

Classified as a strict nature reserve since 1972 — the oldest in the Azores — the Caldeira is now part of Faial’s Natural Park. Descending into the crater is only allowed on guided visits, capped at 12 people per day, precisely to protect the endemic species that survive there, such as Azorean juniper and heather.

The trail that circles the crater

For those who prefer to explore independently, the Caldeira Trail (PRC4FAI) runs about 7 km with moderate difficulty, taking roughly 3.5 hours. The route starts at the Caldeira Viewpoint and follows the rim, lined with hydrangeas in many stretches. At the southern edge, Cabeço Gordo marks the island’s highest point at 1,043 metres, with views over Pico, São Jorge, and Graciosa on clear days.

Getting there

By car, the Caldeira is 20-30 minutes from Horta, driving through the highland scenery typical of Faial’s interior. There’s parking near the viewpoint, from where a pedestrian tunnel leads to the view over the crater’s interior.

Tips for visitors

• Bring waterproof clothing: mist and wind are common even on sunny days along the coast.
• Hiking boots are recommended for the full loop around the crater.
• Book ahead if you want to descend into the interior with a certified guide.

After the Caldeira, head to Capelinhos Volcano on the island’s west tip to see the newest, most dramatic face of Faial’s volcanism.

Learn more about the geology of the Azores.

Featured image — Photo: The Cosmonaut / Wikimedia Commons, CC BY-SA 4.0