The 1st World Orienteering Championships were held in the village of Fiskars, Finland, 1–2 October 1966.

[1] Participants from eleven nations competed in the championships: Austria, Bulgaria, Czechoslovakia, Denmark, East Germany, Finland, Great Britain, Hungary, Norway, Sweden and Switzerland.

Hadler regarded the eighth control, which was located in thick forest, as the most difficult, where the last part of the leg required meticulous map reading and frequent checking of the compass.

Sweden also won the women's relay, which had three legs, with a margin of 21 seconds to silver medalist Finland.

[1] The championships were attended by President of Finland, Urho Kekkonen, who was present at the finishing area.