Intramuros was Manila, for the thousands of Spanish colonists, their families, and their servants - for over 400 years, this walled city guarded the mouth of the Pasig River and served as the seat of the Spanish presence in the Philippines.
The walled city was flattened by American bombers in World War II; only San Agustin Cathedral was left standing by the end of the war. (San Agustin Church was later declared an UNESCO World Heritage Site, together with a number of other churches in the Philippines.) A major (and ongoing) restoration effort has brought back much of what was lost.