Biertan Church is a fortified Lutheran church located in the Transylvanian village of Biertan, Romania. Built in the late 15th century, the church is considered a masterpiece of Gothic architecture in Transylvania and is listed as a UNESCO World Heritage Site.

The church's defensive system is one of the most complex and best preserved in Transylvania, featuring walls, towers, bastions, and a moat. The church was built on a hill, and its fortified walls were designed to protect the village's inhabitants in the event of an attack. The fortifications are reinforced by buttresses and covered with a system of arches and vaults.

Inside, the church is notable for its impressive altar, which was carved in 1483 by the Transylvanian sculptor Veit Stoss. The altar features 28 scenes from the life of Christ and is considered one of the finest examples of late Gothic art in the region.

Biertan Church is also known for its "matrimonial prison," a small room in the church tower where couples seeking a divorce were locked in for two weeks. During this time, they were provided with only one spoon, one plate, and one bed. Legend has it that no couple who was locked in the prison ever divorced after their release.

Today, the church is still used for worship and is a popular tourist attraction, drawing visitors from around the world to admire its architecture and historical significance.