Burning 250 calories cycling is equivalent to burning it running or doing any other activity. A calorie is defined as a "unit of energy". However it generally requires more effort to do this cycling because a bicycle is so much more efficient.

Also, to continue doing this, you would also need to vary the intensity and duration of your workouts, and your workout routine, because as your body adapts (and improves) the same workout will burn fewer calories. For example, a professional marathoner may burn fewer calories running a marathon than another person not in the same physical shape.