While "the most" can be subjective based on how one defines a castle versus a ruins or chateau, the Czech Republic boasts the highest density of castles per square kilometer in the world. There are over 2,000 documented castles, keeps, and chateaux scattered across its relatively small landscape. From the massive Prague Castle—the largest ancient castle complex globally—to the fairytale towers of Hluboká and the gothic ruins of Trosky, the country's history as a crossroads of European power left it heavily fortified. Other countries like Germany or France may have a higher total number of structures due to their larger landmass, but in terms of sheer concentration, the Czech Republic remains the undisputed "Castle Capital" of the world, making it a premier destination for history and architecture enthusiasts.