There are natural thermal spas just to the west of Osijek in the town of Bizovac. They provide much better value than spas closer to Zagreb or Varazdin, and see fewer tourists. The spa is easily accessible by train or bus.
The town of Vukovar is less than an hour away and buses leave very regularly almost every hour, 7 days a week. This town was completely blown up in the recent conflict due to being on the border of Croatia and Serbia and having a mixed-ethnic population, and provides the visitor with a fascinating if not sobering view on the war.
Äakovo and its enormous Cathedral are a half-hour to the south of Osijek. Besides the beautiful Cathedral which completely dominates the town, there are Lipizzaner horses being trained just on the edge of the city a great morning's viewing, and every year in July is the annual folk and embroidery festival which attracts visitors from far and wide.
The KopaÄki Rit (http://en.wikipedia.org/w...) is the biggest natural wetlands in Europe and the birdlife is spectacular. This enormous nature park, located around 15km north of Osijek where the Danube and Drava rivers flow into one another, is a great day out in the countryside - though bring some insect repellent as the mosquitos do bite!! There is no public transport to the park, so take the local bus to Bilje and its a 2-3km walk.
