Kladenský maratón starts and finishes on the track at Sletiště athletics stadium in Kladno, then sends runners out for eight laps through the nearby Lapák forest park. It is a classic 42.195 km marathon, held every September since 2002, with Maratón klub Kladno and A.C. TEPO Kladno behind the race. The setup is simple and runner-focused: a stadium base, a repeated park loop, a six-hour limit, and a field open to runners aged 18 and over.
The course is made of eight 5 km loops on a semi-hard surface, mostly under tree cover, before returning to the stadium track for the finish. Runners from twelve countries have entered, and the race has hosted the Czech Republic Veterans Championship four times. Mulugeta Serbessa, a frequent participant, holds the men's marathon record, while Ivana Martincová holds the women's record. The event also includes children's races, and past starters have included Czech athletics names such as Eliška Klučinová and Vlastimil Zwiefelhofer.