In addition to the P’tit Train du Nord, the Corridor Aérobique is the other signature multi-use trail for running in the Laurentians. This 58 km trail runs from Morin Heights and Amherst. It’s a bit more rugged than the Ptit Train, narrower in sections. The surface is compacted crushed rock with a rather sandy texture, and the average slope gradient is 5%. There’s a good variety — much of it wooded, but some sections pass agricultural fields and are along rivers. There are also spurs to more rugged, hilly trail running.
This map is an excellent resource for trail sections, amenities, and access.