The race takes place in Pallas-Yllästunturi national park which is very close to Ylläs ski center in Äkäslompolo town.
Easiest way to get there is by taking a plane to Helsinki and fly to Kittilä from there. Norwegian may not have flights announced yet but Finnair does and a return ticket from Helsinki is now around 200€. There is a bus connection from the airport to Äkäslompolo, 55 km.
Onnibus had a daily bus route from Helsinki to Ylläs. This is the cheapest way to get there!
You can reach Ylläs by train from Helsinki. Board the night train in the evening, and in the morning you are already in Ylläs. You can also board the train along the route. Kolari railway station is 35 km from Ylläs and there is bus transportation from every train. Find you tickets in VR-onlineshop.
There is also car-carrier train going to Kolari. See the timetable.
Naturally you can also drive. Even though we are above the arctic circle our roads are in good condition.
You can find lots of more infomation about the area and general information about connections from Ylläs website.