Qasba Mosque, 16th-century mosque in Gournadi Upazila, Bangladesh.

The Qasba Mosque is a 16th-century structure featuring nine domes supported by four stone pillars. The building displays three archways facing east and single arches on its north and south sides.

The mosque was built during the reign of Alauddin Husain Shah, an important ruler of the Bengal Sultanate. This construction reflects the architectural style that developed in the region during that period.

The mosque continues to serve as a place of prayer for the local community while being protected as an archaeological monument by Bangladesh's Department of Archaeology. Visitors can witness how this space balances active religious use with its role as a historical landmark that people care for.

The mosque stands in Qasba village, Gournadi Upazila, Barishal District, with a pond in front of it that has largely dried up and was probably dug for ablutions. The Department of Archaeology controls the monument, and prayers are held there regularly, so visitors should time their visit outside prayer times. A shrine to the sage Dut Mallik lies just north of the mosque.

The building features decorative terracotta paintings that adorn its arches, adding visual depth to the structure. These embellishments demonstrate the craftsmanship and artistic techniques used by builders of that era.