Allan Zachariasen (born 4 November 1955 in Odense, Syddanmark) is a retired long-distance runner from Denmark.
He competed for his country in the men's marathon at the 1984 Summer Olympics, finishing in 25th place.
Zachariasen is a five-time national champion in the men's 5,000 metres.
He is the two-time winner of the Twin Cities Marathon, sweeping the first two years of the city-to-city course in the Twin Cities.
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