What is the cycling race Paris-Roubaix famous for?

Explanation

Paris-Roubaix is a classic one-day race, taking place every spring in northern France, between the towns of Compiègne and Roubaix. The route is largely made up of cobbled roads which normally are not of a very good quality which makes the race incredibly difficult, especially if it rains. Lots of crashes and wheel punctures are all part of the fun. The race has been called the Hell of the North, the Queen of the Classics or la Pascale: the Easter race.