Concierge.com's insider take:
An island just ten minutes' ferry ride away, Lokrum was declared a nature reserve in 1964. Legend has it that Richard the Lion-Hearted was shipwrecked here in 1192 after the Crusades. In the 19th century, Ferdinand Maximilian of Hapsburg erected a mansion here. Now, there's a botanical garden (open to the public since 1959) and a hilltop fortress built by the French in 1806, with great views of the city and the islands. A little interior lake, the Mrtvo More (Dead Sea), is perfect for childrenand tends to remain peaceful even when the many beaches on the perimeter are packed.