Region I, also known as the Ilocos Region, is composed of Ilocos Norte, Ilocos Sur, La Union, and Pangasinan. This administrative guide covers its provinces, cities, municipalities, population, geography, and LGU structure.
Region I – Ilocos Region Administrative Guide
Region I, officially known as the Ilocos Region, is located along the northwestern coast of Luzon. It is composed of four provinces—Ilocos Norte, Ilocos Sur, La Union, and Pangasinan—and is known for its rich cultural heritage, coastal landscapes, and well‑preserved historic sites.
This page serves as the official administrative hub for all LGUs within Region I.

by inslands.ph
Region Overview
- Island Group: Luzon
- Regional Center: City of San Fernando, La Union
- Provinces: 4
- Cities: 9
- Municipalities: 116
- Barangays: 3,267+
- PSGC Code: 01000000
Region I is known for its heritage towns, wind farms, surf beaches, coastal plains, and mountain foothills.
Provinces of Region I
Ilocos Norte
- Capital: Laoag City
- Ilocos Norte Administrative Page
- Cities & Municipalities of Ilocos Norte
Ilocos Sur
- Capital: Vigan City
- Ilocos Sur Administrative Page
- Cities & Municipalities of Ilocos Sur
La Union
- Capital: City of San Fernando
- La Union Administrative Page
- Cities & Municipalities of La Union
Pangasinan
- Capital: Lingayen
- Pangasinan Administrative Page
- Cities & Municipalities of Pangasinan
Cities of Region I
Component & Independent Cities
- Laoag City – Capital of Ilocos Norte
- Vigan City – UNESCO Heritage City
- San Fernando City (La Union) – Regional Center
- Dagupan City – Independent Component City
- Alaminos City – Home of Hundred Islands
- Urdaneta City
- San Carlos City
- Batac City
- Candon City
Municipalities of Region I
Region I contains 116 municipalities, organized by province. Each province’s LGU index page provides full listings:
- Ilocos Norte LGUs
- Ilocos Sur LGUs
- La Union LGUs
- Pangasinan LGUs
Geography & Environment
Landscape
Region I features:
- Long coastal plains
- Foothills of the Cordillera
- River basins (Agno, Padsan, Abra)
- Volcanic and limestone formations
Climate
- Tropical monsoon
- Dry season: November–April
- Wet season: May–October
Cultural & Historical Profile
Region I is known for:
- Ilocano cultural heritage
- Spanish-era architecture
- UNESCO-listed Vigan
- Traditional weaving (inabel)
- Coastal fishing communities
- Wind farms (Bangui, Burgos)
Economic Profile
Key Sectors
- Agriculture (rice, corn, tobacco)
- Fisheries
- Tourism
- Renewable energy (wind, solar)
- Trade & services
Major Infrastructure
- Laoag International Airport
- San Fernando Seaport
- Ilocos Norte Wind Farm Complex
- National highways connecting Luzon’s northwest corridor
Internal Links
- Luzon Island Group
- Administrative Divisions
- Cities of the Philippines
- Provinces of the Philippines
- Municipalities of the Philippines
Conclusion
Region I is one of the most historically rich and geographically diverse regions of Luzon. This administrative page provides a complete overview of its provinces, cities, municipalities, and LGU structure, forming a key part of your national administrative silo.