The Groene Halve Marathon begins on Groenstraat in the center of Hamont-Achel, a Belgian municipality near the Dutch border. This road-running event uses a paved, traffic-free, officially certified course, offering races from 100 meters up to the 21-kilometer half marathon. Organized since 1985, the event includes children, casual runners, and experienced athletes.
The youngest runners compete over 100 meters to 1 kilometer within age categories. Adults may select longer distances with electronic timing. The 5K consists of three laps around the center of Hamont-Achel. The 12K is a single large loop through the surrounding area, and the half marathon is also a single-loop race. Medals are awarded to the top three finishers in each category, and children in the youth races receive a participation souvenir.