Region IV-A

Also known as: Region 4-A · CALABARZON · Southern Tagalog Mainland · Manila expansion corridor

Definition

Region IV-A (officially designated as CALABARZON) is an administrative region of the Philippines located in the southwestern portion of Luzon, immediately south and east of Metro Manila. It is bordered by Central Luzon (Region III) to the north, the Pacific Ocean to the east, the Bicol Region (Region V) to the southeast, the Verde Island Passage to the south, and Manila Bay to the west. The region consists of five provinces—Cavite, Laguna, Batangas, Rizal, and Quezon—and is the most populous administrative region in the Philippines, serving as a primary industrial and residential expansion corridor for the national capital. (Official Gazette)

Identities

Source Type	Identity
Wikipedia	Calabarzon
Wikidata	Q13642
DBpedia	Calabarzon
ProductOntology	N/A
Wiktionary	N/A
Library of Congress Subject Headings (LCSH)	Calabarzon (Philippines)
MeSH	N/A
NCBI Taxonomy	N/A
AGROVOC	N/A
Google Scholar	Region IV-A CALABARZON provinces industrial parks real estate Philippines
ConceptNet	N/A
OpenCyc	N/A

Also Known As

Region 4-A
CALABARZON
Southern Tagalog Mainland
Manila expansion corridor

Examples and Analogies

Cavite Industrial Boom: The rapid construction of industrial estates (such as the Cavite Export Processing Zone) and suburban housing projects in Cavite, which has become a primary residential hub for Metro Manila workers.
Laguna Technoparks: The concentration of high-tech manufacturing plants, electronics factories, and automotive assembly lines in Laguna, attracting foreign direct investments. (Official Gazette)

Usage Scenarios

1. BPO Office Siting

An international technology firm rents office space in a PEZA-accredited IT park in Calamba City, Laguna (the regional center of Region IV-A). (Official Gazette)

2. Residential Pre-selling Development

A subdivision developer launches a pre-selling house-and-lot project in Antipolo City, Rizal, targeting middle-income buyers.

Strategies

Research the alignment of major infrastructure projects (like the CALAX and LRT-1 extensions) before purchasing land in Cavite or Batangas.
Verify local LGU zoning ordinances and environmental clearances when developing property near the Laguna de Bay lake basin.
Check the structural building plans to ensure compliance with earthquake metrics due to proximity to the Valley Fault System.

Security and Safety Measures

Do not build structural projects near active volcanic zones (such as the Taal Volcano danger zones in Batangas) without checking national hazard maps.
Ensure all development designs incorporate flood-control infrastructure, especially in low-lying coastal areas of Cavite.
Verify title authenticity directly with the Registry of Deeds in Tagaytay, Imus, or Calamba.

Historical Context

Originally part of the massive Southern Tagalog region (Region IV) established on September 24, 1972, under Integrated Reorganization Plan No. 1, CALABARZON was created when the region was divided in two on May 17, 2002, under Executive Order No. 103 signed by President Gloria Macapagal-Arroyo. This division separated the mainland provinces from the island provinces (MIMAROPA). Since then, CALABARZON has grown to become the industrial powerhouse of the country, generating a significant portion of national GDP. (Official Gazette)

Challenges and Controversies

Severe Traffic Congestion

The rapid growth of suburban populations without matching public mass transit systems has led to severe daily traffic congestion along key highways like SLEX and Aguinaldo Highway.

Loss of Agricultural Land

The continuous expansion of industrial parks and housing projects has resulted in the conversion of coconut and rice fields in Laguna and Quezon, causing friction with local farming groups.

References

Official Gazette of the Republic of the Philippines