Stromovka is the largest park in the city and the most popular park in Prague for jogging. It is about 3km north of Old Town and easily reachable by public transport. The park is mostly flat and it has a series of soft dirt trails to give your legs some relief from the cobblestones. Starting from the Výstaviště Holešovice Tram Station, enter the park. Begin your run heading towards two of the largest ponds in the park. Enjoy the shaded paths as you wind your way along the numerous well maintained paths looping past the Marold panorama (a panoramic image, which depicts a historical battle of Lipan, which took place on 30th May 1434) and back to the start. Add to the run by enjoying some of the other myriad paths in the park.
If you have time after your run check out Výstaviště. It is an exhibition ground which is used for concerts and other events. Additionally, this area houses a planetarium, Tipsport Arena, the Lapidarium of the National Museum, the World of the Oceans Aquarium, Pyramid Theatre and Lunapark, an amusement park in the northern section of this area.
Note: Stromovka Park and Letná Park are within 1km of each other and can easily be combined into a lovely, longer run. In between the parks is the Running Mall, a center for Prague running: store, training center, lounge, run club, classes.