St. Nicholas Cathedral, Eastern Orthodox cathedral in Ahyeon-dong, Seoul, South Korea

St. Nicholas Cathedral in Seoul is a church building featuring Byzantine-style architecture with domes, mosaics, and interlocking decorative patterns typical of Eastern Orthodox sacred structures. The building spans multiple levels and combines traditional religious design with local construction materials.

The first Saint Nicholas church, built for the Russian Ecclesiastical Mission, was consecrated on 17 April 1903 in central Seoul and destroyed during the Korean War. The present Byzantine-style cathedral in Ahyeon-dong dates from 1968, funded by Greek soldiers of the UN mission. In December 2018 Patriarch Bartholomew I visited for the cathedral's 50th anniversary.

The cathedral houses two important icons brought by early Russian missionaries: the Theotokos of Tikhvin and Seraphim of Sarov. These religious works shape the interior space and remain visible to visitors today.

The cathedral stands at 43 Mapo-daero 18-gil in Ahyeon-dong, a short walk from Aeogae Station on Line 5. Shorts and sleeveless tops are not allowed inside; dress accordingly before entering. Opening hours shift with religious events, so check them before setting out.

Greek soldiers stationed as peacekeeping forces under United Nations command contributed funds toward this building's construction. This international collaboration remains an unusual part of the cathedral's history.