Kieselstein Castle (Khislstein), in the middle of the city centre of Kranj, stands above the crossing over the Sava, on a part of the city pier, where there was a fortified area from the ancient period to the early Middle Ages. The walls stood here 1500 years ago. The land was acquired by the Ortenburgs in 1256 and a fortress was built on it. After their extinction in the 15th century, it passed into the ownership of the Counts of Celje and after the death of the last Celje resident, it belonged to the Habsburgs. In the mid-16th century, Baron Janž Khisl bought it and gave it its present appearance, after which the castle was also named. The building was rebuilt in 1952 according to the plans of the architect Jože Plečnik.
The castle building was built between the 15th and 19th centuries, and the castle acquired its present appearance in the 17th century. The south-eastern part of the castle was built during the Turkish invasions. It was incorporated into the city's defensive walls as an integral part of them. A defensive tower was built in the southwestern part at the beginning of the 16th century, to which a two-storey residential building was later added. The castle is adorned with a courtyard and main portal, which were built in the second half of the 16th century, while the courtyard section with arcaded corridors is the result of reconstructions in the 18th and 19th centuries.