A Keirin race during the Zesdaagse (six-day) indoor cycle meeting in the Kuipke velodrome. Keirin racing involves riders slipstreaming behind a pacer on a derny or motorised bicycle to bring them up to a speed of 50km/h. The derny then leaves the track allowing the riders to finish the last 600 or 700 metres on their own. By the time the riders reach the finish line they may travelling at speeds of up to 70km/h. Track cycling is hugely popular in Belgium.