The Sherif Halil Pasha Mosque, more commonly known as the Tombul Mosque, located in Shumen, is the largest mosque in Bulgaria and one of the largest in the Balkans. The mosque complex comprises a main structure (a prayer hall), a courtyard, and a twelve-room annex that serves as a boarding house for the madrasa. The main building starts with a square base, transitions into an octagon, then into a circle at its center, and is crowned by a spherical dome rising 25 meters above the ground.

Inside, the walls are adorned with mural paintings depicting plant motifs, geometric patterns, and Arabic inscriptions, including verses from the Qur’an. The courtyard is notable for its arched colonnade in front of the twelve surrounding rooms, and the minaret stands at an impressive height of 40 meters.