Want a great hike in the Jeseniky mountains of the Czech Republic? Try the Bila Opava.
The trail follows a beautiful little stream, complete with many tiny waterfalls. The second half gets a little adventurous: potentially slippery rocks, occasional missing planks on the stairs suspended above the water, and ladders that may suit long-legged people best.
The trail is only about 5 km from Karlova Studanka up through the valley and to the nearest bus stop at Ovcarna (check bus schedules beforehand on idos.cz--the stop is "Mala Moravka, Ovcarna tocna"). However, since you're already so close, consider continuing on to Praded, the highest peak in Moravia (1491 m), before returning to Ovcarna. It'll stretch your hike to about 12 fantastic kilometers with about 700 m elevation gain. Plan some time at the top to enjoy the views.
You also might want to spend some time in the spa town of Karlova Studanka, just admiring the architecture, strolling the parks, and trying the supposedly healing mineral water.