Santi Primo e Feliciano church at the site is documented since the 12th century. It belonged to a college of canons regular who in 1354, became members of the Congregation of Servants of Mary, and so remained till the 18th century. The convent was suppressed in 1810.
The original structure had three naves, but in the 15th century an additional nave was added. In the 16th century, the church was reduced to a single nave, with demolition of the prior apse. The facade was restored in 1940.
The first chapel on the right has a Virgin and child with Blessed Bertoni and St John the Baptist (1498) by Agostino da Vaprio. The superior lunette has a fresco depicting God the Father. The transept has a large canvas depicting the Martyrdom of St Lawrence by Marcantonio Pellini (1664-1760). The presbytery has two lateral frescoes depicting the Life of Saints Primo and Feliciano (1860) by Bardotti. They depict The Trial of the Saints on the left, and Martyrdom of the Saints, on the right. The first chapel on the left has a Crucifixion with St Pellegrino by Sabbadini.
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.