The Church of St. John (in Estonian: Jaani Kirik) is a large Lutheran parish church in Tallinn, Estonia. It is dedicated to Saint John the Theologian, a disciple of Jesus Christ and the author of the fourth Christian Gospel. Construction began in 1862, and the church was opened in 1867.

Since the Reformation, the main religious tradition in Estonia has been Lutheranism with Catholic statehood and episcopal governance. The national church of Estonia is the Estonian Evangelical Lutheran Church, of which the Church of St. John is a parish church. The motivation for building it was the large size of the existing congregation in the neighboring parish church of the Holy Spirit (sometimes translated as "Holy Ghost"), which by the mid-nineteenth century had more than 14,000 parishioners. Fundraising began in 1851 to build a new parish church in the expanding suburb of the "new" town of Tallinn, at the lower level beneath the ancient city settlement on the hilltop (Toompea). From September 1862, local craftsmen worked on the construction, and the church was consecrated on December 17, 1867.

The green upholstery of the main altar is mostly made of simple velvet, but the main front panel is richly embroidered. Similar sets of alternative colors are used during other periods of the church year.

The church is built in the Neo-Gothic style, with tall pointed arches, and is a very large building encompassing three main naves, with a tall tower at the western end topped with a decorative spire. There is a choir and altar, a small semicircular apse, and a large sacristy. The church is located on the eastern edge of Freedom Square in Tallinn and architecturally dominates the square. The master stonemason and construction supervisor was Karl Sensenberg, and the church’s architect was Christoph August Gabler (1820–1884), a native of the city. Plans to demolish the church were proposed both in the 1930s and 1950s by architects and planners who felt its style conflicted with other buildings on Freedom Square; local opposition prevented the planned demolition on both occasions.

At its consecration, the church received many gifts, including works of art, precious metals (chalices and plates for offerings), and a bell. The church continues to attract gifts of contemporary art, which include church furniture with embroidery in a modern style (altar frontals, superfrontals, and hangings from the pulpit — unusually, the pulpit has two hangings because it has two lecterns, allowing the preacher to choose the appropriate direction in which to deliver the sermon), and modern stained glass windows. A modern stained glass window depicting the Blessed Virgin Mary, located in the Lady Chapel, complements a window on the opposite side of the church depicting the church’s patron saint, Saint John the Theologian. The large altarpiece, rising in the eastern part of the church and depicting the Crucifixion, was created by Professor Karl Gottlieb Wenig, a graduate of the St. Petersburg Academy of Fine Arts, the same institution attended by the church’s architect Gabler.

This is the only Estonian filming location for the "Adventures of Sherlock Holmes and Dr. Watson" series episode "The Treasures of Agra." Now no one remembers why it was impossible to film a suitable church in Leningrad and why it was necessary to bring a group of 15 people to Tallinn for a tiny episode.

Sources:

https://ru.wikipedia.org/wiki/Яановская_церковь_(Таллин)

https://dubikvit.livejournal.com/34231.html

https://www.221b.ru/geo/7-tallin.htm