Switzerland: Mesocco Castle
Switzerland has a fair share of those perfect medieval castles that are clifftop and surrounded by beautiful mountains. The Mesocco castle is just like that – originally started in the 7th century as a small refuge church, it eventually grew to a fortified church by the 10th century, and then a full-fledged fortress by the 13th century. It stands in ruins now but still mostly intact with pentagon walls and five turreted towers. This is one of the largest castles in Switzerland and was considered impregnable in the medieval times (in fact, it was never conquered).