Enduro is a form of off-road motorcycle sport that primarily focuses on the endurance of the competitor. In the most traditional sense ("Time Card Enduros"), competitors complete a 10+ mile lap, of predominately off-road going, often through forestry. The lap is made up of different stages, each with a target time to complete that stage in exactly, there are penalties for being early and late, thus the goal is to be exactly "on time". Some stages are deliberately "tight", others are lax allowing the competitor to recuperate. There are also a variety of special tests, on variety of terrain to further aid classification, these are speed stages where the fastest time is desired. A normal event lasts for 3 to 4 hours, although longer events are not uncommon. Some events, particularly national and world championship events take place over several days and require maintenance work to be carried out within a limited time window or while the race is running. To prevent circumvention of the maintenance restrictions, the motorcycles are kept overnight in secure storage.