The Church of John the Baptist in Kerch is an outstanding example of early Byzantine architecture, dating back to the late 9th and early 10th centuries. This complex structure was fully formed only by the end of the 19th century. The original building, located in the eastern part of the church, was a cross-domed temple with three apses and four pillars. The upper part of the temple stood out with its cross-shaped form, and the corners were lowered. The interior space was divided by columns, allowing for the combination of basilical and cross-domed architectural systems. Such temples began to be built in the 9th century in the eastern regions of the Byzantine Empire. It is not precisely known who built the temple: local craftsmen or invited architects. However, given the complexity of the construction, it is likely that its construction was overseen by the imperial administration and the Patriarchate of Constantinople.

The external walls of the church attract attention with their original limestone masonry, alternating with thin layers of burnt brick and plinth, giving the walls a festive appearance. This method was well-known to Byzantine architects and was used in major public buildings in Chersonesos, Thessaloniki, and Constantinople. The internal arches, the drum of the dome, and the window openings are also made of brick. The church is crowned with a hemispherical dome on a round drum, giving the building elegant outlines. The facades are adorned with arches and pilasters.

The architectural composition of the temple emphasizes verticality. Engineer Rydzevski noted in 1867 the disproportion between the transverse and vertical dimensions, making the church a dominant feature of the urban landscape. Inside, the temple is supported by four cross-shaped pillars and four marble columns with carved capitals. The columns are made of marble with blue veins, sourced from the island of Proconnesus. These elements are likely local spolia used from an older temple. Amphorae were embedded in the church's sails to improve acoustics, some of which were discovered beneath later plaster.

For centuries, burials have taken place around the church. Excavations have revealed dozens of graves dating from the 12th to 15th centuries, although the earliest date back to the time of the temple's construction. Due to its good preservation, the church has long attracted the attention of travelers and scholars. The first mentions of it date back to 1334 when it was visited by Ibn Battuta. In 1634, monk Emiddio D'Artelli d'Ascoli recorded a legend that the church was found in the sea. In 1666, Evliya Çelebi mentioned it in his description of Kerch.

After the annexation of Crimea to Russia in 1783, the study of its antiquities began. By the end of the 19th century, there were two versions regarding the time of the temple's construction. Some scholars dated it to the 8th century based on an inscription on a column, while others believed that the column was taken from an older temple and attributed the construction to the 10th-12th centuries. Archaeological excavations in the 1960s led by T.I. Makarova helped reconstruct the history of the temple.

The site where the church stands was settled in the early centuries of our era. In the 6th century, a basilica was built here, which likely suffered during the Turkic pogrom of 576. By the end of the 7th century, the Bosporus became a battleground between Byzantium and the Khazar Kaganate, leading to the destruction of the baptistery. In the late 9th century, the Church of John the Baptist was built on the ruins of the Khazar period. Archaeological data show that the quarters were built with consideration for the temple.

In the 14th century, the temple was reconstructed, and in subsequent centuries, it was possibly used as a mosque. After Kerch joined the Russian Empire, the church was handed over to the Greek community. In the 19th century, it was repeatedly repaired and expanded. In the 1920s, the church was closed, but it remained a cultural and religious center for the Greek community.

Today, the Church of John the Baptist is a temple of the Russian Orthodox Church and a unique monument of medieval architecture, being the oldest functioning Orthodox church in Eastern Europe.