The church of Agios Nikolaos is located on a plateau just outside Platsa in the locality called Kabinari. It is a domed three-aisle, barrel-vaulted basilica with three equally-sized apses. Two main building phases have been recognised. The first church a three-aisle, barrel-vaulted basilica with a narthex at its west dates to the 9th – 10th century. It was built with hewn orthogonal poros blocks of impressive size. Recent evidence has shown that an earlier, ruined roman structure had been incorporated into the core of this church. The second phase has been precisely dated to 1337-1338, according to the founder’s inscription in the central aisle. This phase included the reconstruction of a large part of the vaulting and the addition of the dome. Smaller scale modifications took place during the early post byzantine period.

The central aisle wall paintings are of exceptional quality, dating to 1337-1338 and sponsored by Konstantinos Spanis, local military commander. Αccording to an inscription the wall paintings of the south aisle, depicting the saint’s life, were made in 1343-1344 (apse semi-dome) and in 1348-1349 (west entrance). The north aisle was dedicated to Theotokos and has been recently dated to the mid- 14th century, right after the completion of the decoration of the south aisle. The sculptures of the church are limited to the decoration of the templa (screens) of the three aisles. They comprise marble fragments from at least two templa, datable to the 11th century (closure slabs) and to the 12th Century (epistyles and kioniskoi); they were placed in the church sometime in the 15th or 16th centuries.