The 20km de Bruxelles is a 20-kilometer city run held in Brussels on the last Sunday of May, organized since 1980. If Belgian national or European elections fall on that Sunday, the race is rescheduled one week earlier due to mandatory voting in Belgium. This event draws a large number of participants, with recent fields approaching 50,000 runners and walkers from over 100 nationalities. Separate practical information is provided for runners, walkers, handisport athletes, teams, mobility, training, and hotels.
The route connects significant landmarks across the City of Brussels and the Brussels-Capital Region, functioning as a city tour alongside the 20-kilometer challenge. Fanfares have been present along the course since the early years. The event has a history of logistical adaptations, including clearer kilometer markers, additional first-aid stations, chip timing, and online registration. Past editions featured a large anniversary cake, a sports village, parade orchestras, a royal starting signal, and one instance nearly canceled due to roadworks. In recent years, the race has also supported charities, raising over EUR2.5 million for good causes.