The Philippines includes 17 official regions, including the National Capital Region (which has not provinces) and 16 regions that contain provinces. Some regions consist of many islands (the country has 7,100 islands). The two largest islands (Luzon and Mindanao) and the Visayas island group are each subdivided into multiple regions. The government defines an official region as "A sub-national administrative unit comprising of several provinces having more or less homogenous characteristics, such as ethnic origin of inhabitants, dialect spoken, agricultural produce, etc." From http://www.nscb.gov.ph/activestats/psgc/articles/con_lgu.asp The regions are:

• Ilocos Region (Region I)
• Cagayan Valley (Region II)
• Central Luzon (Region III)
• CALABARZON (Region IV-A)
• MIMAROPA (Region IV-B)
• Bicol Region (Region V)
• Western Visayas (Region VI)
• Central Visayas (Region VII)
• Eastern Visayas (Region VIII)
• Zamboanga Peninsula (Region IX)
• Northern Mindanao (Region X)
• Davao Region (Region XI)
• SOCCSKSARGEN (Region XII)
• Caraga (Region XIII)
• Autonomous Region in Muslim Mindanao (ARMM)
• Cordillera Administrative Region (CAR)
• National Capital Region (NCR) (Metro Manila)

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