Gunfoundry, Military building in Hyderabad, India

Gunfoundry, also called Top ka Sancha, is a surviving 18th-century cannonball factory at Fateh Maidan. Its lime-plastered brick walls, about 50 feet high originally, taper above 25 feet and are tied with square iron rods. Semicircular brick arches in the lower walls housed the smelting work supervised by General Raymond.

French officer Michel Raymond founded the facility in 1786 while serving the Nizam of Hyderabad. It supplied cannons and artillery to the princely state for several decades during a period of regional conflict.

Locals call the site Top ka Sancha, meaning cannon mould, a name that shifted to Gunfoundry over time. The area now holds the Gunfoundry Museum, and the surrounding division is known for its concentration of Christian missionary schools and churches.

The building stands across from Aliya High School for Boys near Fateh Maidan in the city center. Several bus lines from Nampally and Lakdikapul stations stop in the area.

The walls use unusually thin square bricks bonded with lime mortar. This construction method creates a characteristic joint pattern distinct from other buildings of the period.