In Kilpisjärvi you can snowmobile on trails maintained by Metsähallitus (the national body for the administration of forests), which requires a permit from them. The official snowmobile trail runs from Kilpisjärvi to Hetta. This trail intersects another trail going from Saarikoski to Raittijärvi.
You can also pay to snowmobile on the network of trails maintained by Kilpisjärven Ladut. You can buy the permit for these trails from the Neste petrol station in Kilpisjärvi. Visitors to the area are only allowed to snowmobile on designated trails. Diverting from designated trails will require a separate license.
In the northwest area of Lapland, there are other signposted service trails which also require additional permits. The snowmobile trails are marked with high visibility crosses over ground, and with red poles over ice. You have to be at least 15 to drive a snowmobile. You can approach local tour companies for information about their guided snowmobile safaris.