Achievements He is married to Brit Volden, also a World Orienteering Champion. Thon received gold medals at the 1979 and 1981 Individual World Orienteering Championships, and finished second in 1983. He is also five times Relay champion, as a member of the Norwegian winning teams in 1981 (Thun, Switzerland), 1983 (Zalaegerszeg, Hungary), 1985 (Bendigo, Australia), 1987 (Gérardmer, France) and 1989 (Skaraborg, Sweden). He won the Overall World Cup in Orienteering in 1988, and finished second in 1986. Thon is several times Norwegian champion. He won the classic distance in 1980, achieved bronze medals in 1981 and 1982, and silver medal in 1985. He won the relay with the club IF Sturla seven years in a row from 1979 to 1985. He won the long distance in 1981, 1983 and 1986. He received gold medals in night orienteering in 1981, 1982 and 1984.