Three days is enough for the Bay of Kotor and one inland day. Stay in one place — Kotor — and let the day trips come to you rather than moving hotels.
Morning walking tour of the Old Town, then climb to San Giovanni fortress in the late afternoon when the heat drops and the light hits the bay. Dinner inside the walls.
Half-day boat tour: Perast and Our Lady of the Rocks, the Blue Cave, the submarine tunnels at Žanjice and a swim stop. Afternoon free, or kayak towards Prčanj at sunset.
Up the 25-hairpin serpentine to Njeguši for prosciutto and cheese, the Njegoš Mausoleum on Lovćen, then the old royal capital of Cetinje. Return via Budva if you want an hour in its Old Town.
Enough for the Bay of Kotor and one inland day. Durmitor and the north need at least two more days to be worth the drive.
Kotor. It is central for the bay, has the most day tours leaving from it, and is 20 minutes from Tivat airport.
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