The Church of St Nicholas is located in Isopuisto Park in Kotka city centre. Based on designs by Jakov Perrin, the neoclassical church was constructed between 1799–1801, and it is the oldest building in Kotka today.
The impressive facade consists of pillars for three entries, the bell tower and a cross dome.
The interior is adorned by religious icons and several artefacts. An unusual icon depicts St Nicolas on Kotkansaari with a background view of the Battle of Svensksund.