Short answer
On Terceira, start with Angra do Heroísmo, a UNESCO World Heritage city, with its historic center, cathedral, and fortresses like São João Baptista and São Sebastião. Don't miss the volcanic interior at Algar do Carvão, a unique lava cave, and the Gruta do Natal. For nature, explore the Serra do Cume viewpoint and the Biscoitos natural pools. The island is also known for its bullfighting traditions and festivals. Plan at least two full days to cover the highlights. Check local tourism office for updated opening hours and event schedules.
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