Kotor is a walled Venetian port town wedged between the Adriatic and a wall of karst mountains, its Old Town a maze of marble lanes, Catholic and Orthodox churches, and fortifications that climb straight up the cliffside behind it.
Late May, June, or September, when the bay is warm enough to swim but the cruise-ship crowds and peak summer heat haven't taken over the Old Town.
Order Njeguški pršut (air-dried prosciutto from the mountains above the bay) with local cheese, or crni rižot — black risotto made with cuttlefish ink — at a konoba near the harbor.
Base yourself inside the Old Town's stone walls near Trg od Oružja, within easy walking distance of the cathedral, the harbor, and the base of the fortress climb.
Climb the city walls to St. John's Fortress before 7am — there's almost no shade on the stone steps, and the ticket line backs up fast once the first cruise ship tenders start landing.
Read more in Kotor Travel Guide: Venetian Old Town & the Bay of Kotor.