Agios Nikolaos is the patron saint of Upper Trikala.
We do not know the exact date the church was built, but we do know that it was renovated in 1805 by Panoutsos Notaras. The church of Agios Nikolaos is of the triconch type; in other words, it has three apses, one in the sanctum and the other two in the chanters area. The triconch type of church was common during the 10th century at Mount Athos.
The roof of Agios Nikolaos was initially covered with lead, but was later covered with tiles. The church has a narthex and a woman’s area (gynekonitis) (these were not part of the original structure but were added later) and a dome. The church’s icon stand is woodcut.
The church has murals that were created by N. Sandorinaios, and the technique applied to these murals reveals an obvious western influence.
There are also a number of noteworthy portable icons.