San Nicolás church stands in the suburb of the same name outside the walls, a medieval quarter inhabited by Christians and dedicated to agriculture and sheep farming. It also had a large number of Mudejar residents. It was built in Caleno granite in the late-Romanesque style of Ávila between the second half of the 12th century and the beginning of the 13th. The upper end and porches remain from the original construction.
The three entrances take the form of semi-circular arches with archivolts. The northern entrance is the most ornamental and is decorated with wedges, palmettes and ivy leaves, which are very typical motifs on Romanesque churches in Zamora. The capitals of the archivolts have plant motifs.
The tower is built on to the upper end from the North. It is divided into three bodies and shows two periods of construction. A Vetton animal sculpture was reused for the plinth.
It has three naves: the central nave opens into a large apse and the side naves into rectangular chapels. Except for the upper end, the temple was covered with Baroque-style plasterwork in the 17th century.
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.