 There are several prominent 5K race series, including The Color Run, an international, mass participation, city-based series involving coloured water showers, and the parkrun series, which is a worldwide network of free-to-enter, volunteer-led races occurring each weekend, originating in the United Kingdom.Unlike longer road races, such as the 10K run and marathon, the 5K distance is not commonly contested by elite distance runners.The Carlsbad 5000 is one of the few races that attract competitive elite fields and has seen several world bests for the distance (prior to the IAAF's 2018 decision to begin recognising world records for the 5K).