For families, you can’t do better than Umag on the northern coast of Istria. Acres of land along the coast have been turned into a sort of giant theme park. Nearly every hotel has at least one pool, sometimes more. Plus there’s minature golf, paintball, tennis, pingpong and watersports. Although the “beaches” are actually rocky slabs, the water is shallow and safe.  Looking for a quiet, romantic hideaway? Move along. There’s nothing here for you.