The above video is a brief look at a Six Day Bicycle Race held in Tilburg, in The Netherlands. If you click on this Vimeo link you can watch it in full screen mode.
Six Day racing started in America in the late 1800s and the reason it was six days was to avoid riding on a Sunday and offending the religious element.
Originally riders rode continually for six days on a tiny indoor track, but in 1898 the states of New York and Illinois, alarmed for the health and well being of the competitors, ruled that no cyclist could ride more than 12 hours a day.
The promoters, not willing to open the event half a day, realized if they made it a relay race with teams of two riders, each would only be riding the required 12 hours. Speeds rose, distances grew, crowds increased, money poured in.
This type of relay race became known as a Madison, after Madison Square Garden in New York where these races were held. In France it is known as the "American race" (course à l'américaine) and in Italian and Spanish as Americana.
Six Day races are no longer held in America unfortunately, but they are in Europe during the winter months when it is the off season for professional riders. I went to quite a few held at London’s Wembly Arena in the 1950s through the 1970s.
A small ten laps to the mile wooden track is constructed in an indoor stadium. Racing is no longer continuous, but is a series of different events with the same riders competing, and held every evening for six days.
The last main event of each evening is usually a one hour Madison. Because the track is only a tenth of a mile around, it is possible for a rider to break away from the pack, and by riding flat out for several laps will catch the tail end of the pack, thereby gaining a lap.
The number of laps ridden are added up for the complete six days, and a clear winner comes out. Both riders of a team are on the track at the same time. One is racing; the other is circling slowly high on the banked track, resting and conserving his energy.
At any time the riders choose they may change off by touching the other rider. This usually takes the form of a hand sling. The rider in the race, as he approaches his team mate, grabs his hand. This has the effect of slowing him down. He then slings the fresh rider into the race.
Other races throughout the evening might be:
A Scratch Race: All the riders start in a pack and race over a predetermined number of laps. This is not a relay, but team members may block a chasing group, if the other team member is in a break. Or one team member may lead to other out in the finishing sprint.
The Devil Take the Hindmost: A race where the last rider over the finish line each lap is eliminated until you only have two riders left who sprint it out for the finish.
A One Lap Time Trial: This is shown in the video where one rider gives his team mate a hand sling for a flying start for timed lap.
Derney Paced: A Derney is a specialist built motorcycle for pacing in these type of events. The Derney has pedals so its driver can accelerate smoothly by pedaling. It is a highly tactical event, the rider with the inside track has less distance to travel than someone overtaking on the banking. The Derney driver has time his attack precisely; if he accelerates too fast he will drop his rider.