The minimum age varies per distance:
4km – Family Run: Min. age 5 years (or turning 5 in this calendar year)
4km – Beginning: Min. age 12 years (or turning 12 in this calendar year)
7km: Min. age 13 years (or turning 13 in this calendar year)
13km: Min. age 14 years (or turning 14 in this calendar year)
19km & OCR-series: Min. age 16 years (or turning 16 in this calendar year)
42km Iron Viking: Min. age 18 years
60km Ultra Viking: Min. age 18 years