The Gothic Cathedral of St. John the Baptist and St. John the Evangelist received its present-day shape as a result of the multi-stage construction which was interrupted at the turn of the 16th century, after 200 years of works. In the Middle Ages it was the most important church in Toruń as it had the function of the Old Town parish church congregating worshippers from the entire town.
In mid 16th century it was temporarily taken over by Lutherans, later, for several years, it served as a place of worship for both denominations as both the Protestant and Roman Catholic services were held there. From the late 16th century to the second half of the 18th century the church was in the possession of Jesuits. In 1992 the church received the status of a cathedral basilica – the main church of the Toruń diocese formed by the Pope John Paul II.
The spacious interior of the church is filled with masterpieces of sacral art. In the presbytery, built in the first half of the 14th century, there are 14th century Gothic paintings depicting the patron saints of the church – St. John the Baptist and St. John the Evangelist, as well as a monumental, multi-theme medieval painting presenting the Last Judgement. The high altar of St. Wolfgang, the stained glass windows and the soaring vault also date back to the medieval times. The nave and the aisles of the cathedral contain several Renaissance and Baroque altars and numerous epitaphs of Toruń burghers and noblemen from the surrounding area. The greatest attraction, however, is the chapel containing a baptismal font at which Nicolaus Copernicus was baptized in 1473. About one hundred years later a Renaissance epitaph with a portrait of the great astronomer was placed here. In the Napoleonic times, the chapel received the oldest, though rather unimpressive, bust of Copernicus, carved in 1766. Behind the bust, on the wall, there is a mural indicating that it was is also the burial place of the heart of the Polish king John I Albert, who died in Toruń in 1501.
The cathedral can also boast the magnificent Tuba Dei bell ( God's Trumpet) weighing over 7 tons. When it was cast in 1500 and suspended in the cathedral belfry it was the largest bell in this part of Europe. According to a legend, its creation was connected with the fear of the impending doom and the great bell was to plead with God to postpone the imminent Apocalipse. The sound of Tuba Dei for centuries accompanied the most important events and ceremonies in the history of the town. Therefore, it is no wonder that in the 18th century, the city council raised a tremendous amount of money to pay off the Swedish army stationed in Toruń and prevent the bell from being taken away to Sweden. Today, Tuba Dei is used only a few times in the year, on rare occasions, as the vibrations caused by its low tone threaten the stability of the bell tower. While climbing to the top floor of the tower, which offers a stunning view of the Old Town, one can pass the bell and touch its clapper. It is said to be the best way to make a wish come true.