Positano in December

April through June is your sweet spot. Weather's warm enough for swimming, restaurants are open, but you're not fighting for space with every influencer in Europe. May is particularly lovely — wisteria blooms everywhere and hotel prices haven't hit summer insanity yet. September and October work too, though some beach clubs start closing by mid-October. Avoid July and August unless you enjoy paying €50 for a beach chair and waiting 45 minutes for a table at lunch. Winter has its charm if you're into dramatic storms and empty streets, but half the restaurants shut down and ferry service gets sketchy.