The peninsula of Hanko is the most southern point of Finland (like Kushka on the Afgan border for former USSR). However unlike the Kushka (where I has been too), Hanko is a resort and very pleasant place in many respects, including presence of various historical monuments.
How to reach - see Sveaborg and Salpa Line sectors of this site.
Further go to "royal road" to Helsingfors, than around of it on "III ring" and to 51-st or 25-th highway. See the road indexes, you are in Europe, but not in the West Siberia, thank God!