Pasig Foundation Day, also known as Pasig City Day, is observed in the Philippine city of Pasig every July 2. This special non-working holiday commemorates the city's founding anniversary, which dates back to July 2, 1573, when Augustinian missionaries established the settlement known as Ciudad-Municipal de Pasig. The celebration includes a thanksgiving Mass at the Immaculate Conception Cathedral of Pasig, official ceremonies, agricultural fairs, civic parades, exhibitions, concerts, dance competitions, and various sporting events. The holiday has been celebrated since 2004, highlighting the city's rich history, which includes its early community co-ruled by Rajah Lontok and Dayang Kalangitan, and its significance during the Spanish colonial period and subsequent American control. Pasig's name reflects its geographical location along the Pasig River, derived from a Proto-Malayo-Polynesian term meaning "sandy bank of a river."