Mikulášská dvacítka is a traditional 20-kilometre running race held at the Baník Stříbro stadium in Stříbro, western Czechia. The athletics club Baník Stříbro organizes it. Runners are divided into age and gender categories but start together. The race is open to runners without health restrictions. One reported edition had 45 starters, including 12 women, with cold weather around seven degrees Celsius and rain arriving near midday.
The route begins at the stadium, proceeds along the road past the Sv. Petr area toward Butov, descends toward the dam, passes between cottages, crosses a wooden footbridge over a stream, and ascends onto a forest haulage road. Participants run as far as the railway bridge near Pňovany, turn before the bridge, and return the same way; crossing the bridge is prohibited. Approximately two-thirds of the course is asphalt, with the remainder on forest paths and trails. Every finisher gets a commemorative certificate and a small prize, while the top three in each category receive material prizes.