The Orthodox Church of St Constantine and Helen in Plovdiv was built in 1832 on the site of an old church.
The church is located in the Old Town, near the eastern gate of the ancient acropolis (Hisar kapia). A medieval room (probably a crypt) was discovered under the altar of the present building, and the foundations of an old church from the 13th-14th centuries were found in the neighbourhood. It is possible that the inhabitants of Filipopolis (former name of Plovdiv) built a church on this site immediately after the official decree of Emperor Constantine the Great on Christianity.
The building was badly damaged by a fire in the XVII century, so in 1810 Todor Moravenov found here a dilapidated building without a roof. For twenty years he raised funds to rebuild the church. In 1830-1832, extensive reconstruction of the church was carried out. It was named in honour of two saints - Emperor Constantine, who declared the Christian faith as the state religion of the Roman Empire, and Helen - his mother.
With regard to the architecture of the temple, the most interesting is the octagonal five-tiered bell tower with many arched windows, rising above one of the church walls.
The temple was decorated by such masters as Zacharias Zograf, Stanislav Dospevski, Atanas Gyudjenov, Nikola Odrinchanin and others. The church preserves a carved wooden iconostasis, covered with gilding, by the outstanding Bulgarian master I. Pashkul.
