The castle was built by the Czech and Holy Roman Emperor Charles IV starting in 1348. It was his most important castle, built not mainly for soldiers to live in but as a special treasury — a secure place to store the sacred relics and crown jewels of the kingdom.
Karlštejn has three main towers, each taller than the one before it. The tallest is the Great Tower, and inside it is the Chapel of the Holy Cross — a small room whose walls are covered with semi-precious stones and beautifully painted panels. It took artists many years to decorate.
The castle sits on such a steep and narrow ridge that no enemy army ever managed to capture it. The walls are extremely thick, and the only way up was a single winding path. Today, visitors walk up that same path through the forest to reach the gate.
In the valley below the castle, a small village of the same name grew up to house the people who looked after the castle. From the village, you look straight up through the treetops at the white walls and towers high above — it looks just as dramatic today as it did 600 years ago.