Zamboanga Peninsula (Filipino: 'Tangway ng Kasambuwangaan') is a peninsula and an administrative region in the Philippines, designated as Region IX. The region consists of three provinces, namely, Zamboanga del Norte, Zamboanga del Sur, and Zamboanga Sibugay, its component cities of Dipolog, Dapitan, Pagadian, and Isabela and the highly urbanized city of Zamboanga. The region was previously known as Western Mindanao before the enactment of Executive Order No. 36 on September 19, 2001. Pagadian City is the regional center, while the largest city is Zamboanga City.