held at 2,800 meters. All events for women are currently run at 1,600 meters. There are usually small variances in distance based on the size of the track. Race grades A race meeting at any given keirin velodrome in Japan is assigned a grade. The highest graded events are GP, GI (G1), GII (G2) and GIII (G3), reserved only for S-class riders. Underneath those are FI (F1) events, which are open to both S-class and A-class riders. The lowest graded events, FII (F2), are reserved for A-class riders. The GP grade designation is reserved for the Keirin Grand Prix, a three-day meet held at the end of December for the year's top keirin competitors. The meet ultimately concludes with the Grand Prix race itself, which determines the annual Keirin racing champion. As of 2018, a selection committee determines the competitors for the Grand Prix race using the following priority: Winners of each of the six GI events during the year, Japanese medal winners of individual cycling events during the Summer Olympic Games, if they are held in the same year, Competitors specifically recognized by the selection committee, and Competitors that have earned the most prize money from Keirin events during the year. Also part of the Grand Prix meet is the Young Grand Prix, which is open to the best of those that have begun competing in Keirin within the last three years; it is the only Keirin race of the year in which both S-class and A-class compete in the same race. A new addition to the meet in 2012 was the Girls' Grand Prix for the sport's top female competitors. Another prestigious event on the annual keirin racing calendar is the GI Japan Championship. Held every May over a period of six days, it is the longest single race meeting of the year. Each of the keirin velodromes are generally permitted to host one event per year of either GI, GII or GIII designation. The remaining events at each track consist of a combination of FI and FII races for a total of approximately 70 race days per year. On average there is one GI or GII event every month and one GIII meeting per week on the annual calendar. Top Keirin events As of 2019, the top events on the Keirin racing calendar are as follows: Race schedule Keirin velodromes follow the same basic schedule of races