Take the Perast and Our Lady of the Rocks trip if you want the postcard bay: a baroque town, a man-made island with a 17th-century church you can walk inside, and the classic Boka view — 3 hours, from €25–€30, calm water, runs April to October. Take the Blue Cave trip if you want swimming and sea caves: the cave glows electric blue in the late morning, and the route usually adds Mamula island and Žanjice beach — 3–4 hours, from €30, May to September, and it needs calm sea so it can be rerouted. Full-day trips from €35–€45 combine both, which is the best choice if you only have one boat day.
The Blue Cave sits outside the bay on the Luštica peninsula, exposed to open sea. Perast is inside the bay where the water is almost always flat.
The cave's colour is strongest between roughly 10:00 and 13:00, which is also when it is busiest — early small-group boats get there first.
See and book these experiences
Yes if the sea is calm and you like swimming — the water glows a vivid blue and you swim inside the cave. If you are prone to seasickness or travelling with small children, the Perast route is the safer choice.
Yes — full-day boat tours from Kotor, Tivat or Herceg Novi cover both plus swimming stops, from €35 per person.
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