Zadar is one of the best bases on the Dalmatian coast for day trips. The Kornati Islands — a thinly populated archipelago of ninety bare rocky islands — are accessible by boat from Zadar marina; expect a full-day excursion with lunch on board. The waterfalls of Krka National Park are an hour to the south by car or bus. The fortified hill town of Nin and the long sandy beach at Queen's Beach are a 20-minute drive north.
Plitvice Lakes — the most famous national park in Croatia — is about two hours inland by road and is the most popular day trip out of Zadar. Go early; the buses arrive by 10am and the boardwalks fill up fast.