Find a hill, any street. The actual distance doesn't matter. You don't need to go exactly 200 meters. Use a watch or just count 10 seconds. You should rotate different workouts. Experiment with sprints as short as 30m, as high as 300m. Vary the number of intervals, and the rest, just like weightlifting. You want your body to be well-rounded. Rarely should you exceed 6 intervals.