Concierge.com's insider take:
Hvar Town has become the party capital of the Adriatic. This is due in large part to Carpe Diem Bar and Lounge, a longstanding outdoor-indoor spot (pictured) whose afternoon après-beach scene often spirals into an all-night dance party. It's on the international DJ circuit, and sees a beautiful crowd of Europeans in their 20s and 30s who know one another from other global hot spots—"Brigitte, didn't I see you last week in St. Tropez?" (385-21-742-369; www.carpe-diem-hvar.com).
A few other nightlife spots lack Carpe Diem's following but stand out as fun places to let loose after a beach day. In Split, Puls 2 is one of a cadre of modish cafe-bars inside Diocletian's Palace. Locals and tourists mix under the stars drinking the best local beer, Karlovačko (1 Buvinina; no phone). In Bol, on the island of Brač, the action is at Hotel Kaštil's Varadero Cocktail Bar, an open-air nightspot with good DJs for when you're up dancing and comfortable wicker furniture for when you're not (385-21-635-996; www.kastil.hr). In Korčula Town, one of the coolest bars you'll ever experience is Massimo. It's actually part of the ancient fortified seaside wall: You climb a ladder to the crenellated tower, which looks over the water and town; bartenders serve drinks via a pulley system (385-20-715-073).