Since prehistoric times Finns defended themselves on fortified hills. Couple of them reside close to the capital and are great destinations to visit.
"Not all those who wander are lost" -J.R.R. Tolkein
Between 1914-18 terrestial fortifications were built all around Helsinki. Interesting sites remain in the forests surrunding the capital.
WWI FORTIFICATION LINE OF HELSINKI
Ancient mailing route between Norway and Russia all the way with historical treasures; manors, old villages and inns.