During the 1940s Harry Snell was one of the best amateur cyclists in Sweden. Snell won his first national title in 1942 with victory in the team event at the road race championships, before winning his first individual title a year later. He won a further three individual road race titles (1944, 1948, 1950), along with team titles in 1944 and 1948, and an individual time trial title in 1945. Other important victories included back-to-back wins at the Mälaren Runt one-day race in 1944 and 1945, and winning the Nordic Championship road race in 1946. Snell had arguably his biggest win of his career in 1948 when he won the amateur road race at the UCI World Championships in Valkenburg, Netherlands. A few weeks earlier he had also finished 18th in the road race at the London Olympics.