REGION IV-A or CALABARZON is composed of five (5) Provinces namely: CAvite, LAguna, BAtangas, Rizal and QueZON  plus Lucena City which is the first Highly Urbanized City. The Region is in southwestern Luzon, just south and east of Metro Manila and is the second most densely populated region. CALABARZON and MIMAROPA were previously combined together as Southern Tagalog, until they were separated in 2002. Executive Order No. 246, dated October 28, 2003, designated Calamba City as the regional center of CALABARZON. The largest city of CALABARZON Region and the second highly-urbanized city is Antipolo City.

Region IV-A had a very important role in the history of the Philippines. Philippine independence was held by the first Philippine president, Gen. Emilio Aguinaldo, in on June 12, 1898. People from Batangas, Cavite and Laguna were a part of those who first revolted against the Spaniards for freedom. While the Philippines' national hero, Dr. Jose P. Rizal, his brother, Paciano Rizal and Vicente Lim was also born in Calamba City. Apolinario Mabini, was born in Tanauan City, Batangas The eight primary rays of the sun found in the Philippine Flag represent the first eight provinces (Batangas, Bulacan, Cavite, Laguna, Manila, Nueva Ecija, Pampanga, and Tarlac) that sought independence from Spain and were placed under martial law by the Spaniards at the start of the Philippine Revolution in 1896.