Octant Furnas (formerly Furnas Boutique Hotel)

Furnas sits in a collapsed volcanic caldera in the east of São Miguel, and the ground there is still working. Steam comes out of the earth in the middle of the village, the lake nearby is used to cook cozido by burying pots in the hot soil for hours, and the whole valley holds one of the largest concentrations of hot springs in Europe.

Octant Furnas is a reworking of a historic thermal centre, and the building is good in its own right: large glass windows, calm interiors, colours and textures taken from the springs themselves. Guest rooms mix contemporary furniture with vintage pieces and hang minimalist nature photography.

The pools are the reason to book. Indoor and outdoor thermal pools, fed by the volcanic water, and open 24 hours a day. That last detail changes the stay entirely. You can be in hot mineral water at midnight under a sky with almost no light pollution, or at sunrise before anything else on the island is awake.

The spa runs to ten treatment rooms with a floatbed, Shirodhara, Vichy shower, hydro massage, sauna, hammam and a gym. Terra, the restaurant, cooks Azorean and Portuguese food with organic island produce, and there is a cocktail lounge hung with lanterns and greenery.

There are 55 rooms. Pets are allowed.

For position, the Caldeiras das Furnas are a five-minute walk and the Terra Nostra botanical park about fourteen. Lagoa das Furnas, where the cozido is cooked, is a short drive. Ponta Delgada and the airport are about 45 minutes away, so this suits a few nights in the east of the island rather than a base for all of it.