Langgar Merdeka is a building donated by H. Mas Hadi, which previously belonged to a Chinese individual. The construction of the langgar (small mosque) began in 1942 and was completed on February 26, 1946. During the Dutch Military Aggression in 1949, the langgar was used as a base by Indonesian freedom fighters and was temporarily renamed Langgar Al Ikhlas. However, after the military aggression ended, its name was changed to Langgar Merdeka (Merdeka means "freedom" or "independence").