The objective of red-lining is to hike all the trails in a given area. In this particular case, it is referring to hiking all of the trails in the AMC White Mountain Guide. The term "red-lining" comes from taking a map or set of maps of a given area and highlighting the trails with a red magic marker as the trails are completed. It can be accomplished any time of the year and in any order. Trails can be completed all at once or in segments. Any version of the AMC White Mountain Guide can be used although you are encouraged to use one of the more recent versions.

There are approximately 1,420 miles of trails described in the AMC White Mountains Guide. Anyone completing this challenge will inevitably hike many, many more miles. The trails criss-cross in so many places it is impossible to hike them all without repeating some trails.

The White Mountains are so beautiful. Unfortunately, there are some areas of the Whites that are seldom visited because a certain trail does not lead to a peak that is on a list. One of the hopes of this website is to encourage hikers to give the most heavily used trails a bit of a break and use some of the trails that are lightly used. This is better for the trails and provides an uncrowded hiking experience.