Cathedral of the Dormition of the Theotokos, the main cathedral of the Old Calendar Bulgarian Orthodox Church which follows the traditional Eastern Orthodox liturgical calendar and rejects ecumenism. The OCBOC is not recognised by any other Orthodox jurisdiction. [3072x2304]
Hildesheim Cathedral, Germany, constructed in 1020. The rose that climbs the apse is believed to be the oldest living rose bush in the world, at around 700 years old. [3515×5273]
All Hallows-by-the-Tower, claimed to be "the oldest church in the City of London", founded in AD 675 and rededicated after extensive reconstruction in 1957. [1944x2529]
The Church of the Transfiguration at Lagkada in the Pelopponese (Greece). It's the most significant late Byzantine (14th century) church built in the Mani [2622x2124][OC]