Criterium in the night is the most popular winter training among us. There are several reasons for which it's so popular. Firstly, it's easier to distinguish roads' surface during the night in comparison with the daytime. Because in the daytime, it's difficult to see unevenness on the roads as everything is white. But in the night, it becomes easier to distinguish it with headlights. So you can speed more safely in the night. Secondly, you can gather many participants who work or go to school in the daytime. Riding with many opponents makes it fun. Finally, the road condition is better than the daytime as the temperature is lower and there's no sunlight. Therefore, the nocturnal criterium has become so popular.
Usually nocturnal criterium is held in residential areas that are under construction. That means that it takes place in areas where nobody lives. Because we imagine the inhabitants won't like it and it would be dangerous if we do a criterium training in an area where someone lives. In addition, we need short circuits as studded tires are extremely heavy. A normal circuit for summer criterium is too long for heavy studded tires. It's easy to find short circuit in residential areas. Therefore, residential areas which are under construction are suitable for the winter criterium. Hence, the training place changes every year as we have to move when the residential areas' construction is achieved.
This type of training was invented by Tesseract in January 1997. Today, maybe only few people know who's begun this training. The very first criterium was held in Miyanomori. That January, there was very few snow and the residential area under construction in Miyanomori was the only area where the roads were snow covered. So he wanted to use this district for training. Therefore, he gathered his teammates to do training there. But the roads were too steep (about 15%) that it was difficult to ride in group. But it was kind of success.
Since then, we do criterium training in the night because it was fun. Nowadays, this training style was wide spead, many groups do it. It's really fun. As a circuit is short, the victory depends on the drifting technique. Every rider in the front group does drifting in order to pass corners fast. So you better practice drifting to win the criterium on snow.
Examples of nocturnal criterium: