The must-see places are Sete Cidades, the Lagoa do Fogo area, Furnas, and Nordeste. It’s difficult to see them all in one day, especially with the fantastic hidden trails and views that would take a day or half a day to reach each location.
Sete Cidades and Lagoa do Fogo are the areas with the most off-road trails outside the usual tourist routes. In both locations, you also have the opportunity to enjoy the thermal baths.
On the Sete Cidades route, there’s Ferraria; in Lagoa do Fogo, there’s the old caldera or the Ribeira Grande calderas; and in Furnas, there’s the Terra Nostra botanical garden or the Poça da Beija thermal pools.