The Abbey of the Santo Spirito (Holy Spirit), built by the Norman Count Ruggero and his wife Queen Adelasia in 1092–1098, was consecrated in 1153. It has been greatly altered in subsequent centuries. The original outlines are still identifiable to the rear, where its characteristic massive jutting apses can be seen. These are separated by flat pilasters and connected by a series of small arches. The left-hand entrance has an ogival portal from the 13th century. The lunette once contained a figure of Christ Blessing, which was eventually moved inside the Abbey. Notable are the rectangular nave and wooden-beamed ceiling. The walls and the apses have frescoes attributed to the 14th century. The vault of the apse shows a 17th-century figure of Christ Pantocrator.
References:Celje Castle was once the largest fortification on Slovenian territory. The first fortified building on the site (a Romanesque palace) was built in the first half of the 13th century by the Counts of Heunburg from Carinthia on the stony outcrop on the western side of the ridge where the castle stands. It had five sides, or four plus the southern side, which was a natural defence. The first written records of the castle date back to between 1125 and 1137; it was probably built by Count Gunter. In the western section of the castle, there was a building with several floors. Remains of the walls of this palatium have survived. In the eastern section, there was an enclosed courtyard with large water reservoirs. The eastern wall, which protects the castle from its most exposed side, was around three metres thicker than the rest of the curtain wall. The wall was topped with a parapet and protected walkway.