f8b46ce4_lub__General_Event_Information__Description
[0] Long [Length] 10 km or more [Difficulty] Any, usually Advanced [Description] 
As the name suggests, a Long-O is a course that covers a greater distance than usual. Typical distances 10 km or more. Although the course can be of any level of difficulty, a Long-O often combines a lower level of difficulty with a longer course.
Minnesota Orienteering Club: General Event Information
Description