Saint-Petersburg -> Helsinki (by car)
Helsinki -> Stockholm (by ferry)
Stockholm -> Oslo (by car)
Oslo -> Bergen (by car)
Bergen -> Laerdal (by car)
Laerdal -> Geiranger (by car)
Geiranger -> Alesund (by car)
Alesund -> Trondheim (by car)
And then we will take Hurtigruten express ferry and travel along Norway coast to the north of Norway (Kirkenes) - 5 days
http://www.hurtigruten.co.uk/route_maps/norway_classic.asp
Kirkenes -> Saint-Petersburg (by car, through Finland, 3 days)
Enjoy!