The Great Lakeland 3Day™ (also known as the GL3D™) is a small but adventurous three-day mountain marathon with a relaxed and friendly atmosphere that attracts both runners and long-distance walkers. The event has taken place most years in the Lake District since 1998.

This short film by Reeltime Adventure, from the 2012 event provides a flavour of what competitors should expect.

The GL3D™ has built a reputation as a relaxed and friendly event with an emphasis on long mountain journeys, spectacular scenery and enjoying an amazing mountain experience rather than complex navigation. Competitors should expect mountain trails and footpaths, along ridges and through valleys, rather than contouring and bogs.