Celje, also known by the German name Cilli, is the fourth-largest city in Slovenia. It is a regional center of the traditional Slovenian region of Styria and the administrative seat of the City Municipality of Celje. Celje was known as Celeia during the Roman period. Early attestations of the name during or following Slavic settlement include Cylia in 452.

The town's tourist sights include a Greyfriars monastery founded in 1241 and the Upper Celje Castle. The parish church, dating from the 14th century, with its beautiful Gothic chapel, is an interesting specimen of medieval architecture. The so-called German church, in Romanesque style, belonged to the monastery, which was closed in 1808. The throne of the counts of Cilli is preserved here, and also the tombs of several members of the family.