Long Tiny Loop is an international fitness challenge to find “the longest possible non-self-intersecting loop within the smallest possible region, without revisiting any streets or intersections”. The explanation for Long Tiny Loop is a little complicated but I can assure you that once you explore the maps at the top of the competition leaderboard you will quickly understand the concept. Basically you need to create a long but compact route which doesn’t require you having to travel over the same ground more than once.

Source: Maps Mania: What is the Longest Tiny Loop?