Lena Pillars in Russia, also called Lena's Stone Forest, is a natural rock formation along the banks of the Lena River about 60 km upriver from Yakutsk, Siberia. The pillars are metres and extends along the river for about 80 km.
One of the most famous castles in the world Olavinlinna in Finland was built to protect the country from an invasion by Russia It is the northernmost medieval stone fortress still standing in the world.
Gorges de l'Areuse, Switzerland The Val de Travers is a Jura mountain valley perpendicular to the main valleys (hence the name). The river Areuse has cut itself steeply through the soft limestone and clay sediments. It's one of those Roman bridges too.