The Cathedral of St. Martin and St. Nicholas in Bydgoszcz is a Gothic church from the 15th century, considered the most important monument of Old Polish architecture in the city. It serves as the cathedral of the Diocese of Bydgoszcz and is also the sanctuary of Our Lady of Beautiful Love, housing identity-forming Marian images. The history of the church dates back to 1346 when a parish was established in Bydgoszcz. The first wooden temple survived until a fire in 1425, after which the construction of the current brick church began, completed in 1466. Over the following centuries, the church was expanded and beautified. At the turn of the 15th and 16th centuries, the roof was raised, and the interior was transformed with new Baroque decorations and altars. In the 18th century, the temple suffered from fire and devastation, but despite changes in power and the dissolution of religious orders, it remained an important site for the religious life of Bydgoszcz. During the Prussian period, the church became the only parish church for Poles, strengthening its role as a center of worship and national identity. After World War II, the cathedral underwent numerous renovations, and extensive conservation work elevated its status. In 1999, Pope John Paul II granted the church the title of co-cathedral of the Archdiocese of Gniezno, and in 2004, it was transformed into the cathedral of the Diocese of Bydgoszcz. An interesting fact is that in 2018, a treasure consisting of 17th-century artifacts and coins was discovered, highlighting the rich history of this place. With its richly decorated interior, the cathedral continues to fulfill important cultural and religious functions, attracting both the faithful and tourists.