The City in Brief
Map 1. Location Map of Isabela City
Isabela City is located in the northern part of the province of Basilan (North 63 degrees, 45minutes latitude and South 121 degrees, 58 minutes latitude). Located in the waters of the Celebes Sea, the Moro Gulf and the Sulu Sea, it is situated at the tip of the Zamboanga Peninsula, approximately 17 nautical miles south of Zamboanga City. It is separated from Zamboanga to the north by the Basilan Strait.
Isabela is bounded by Lamitan to the east, Lantawan to the west, and Sumisip and Maluso to the south.
The city is a melting pot of Basilan owing to its geography and history. With a population of 112,788 as of 2015, Isabela City is home to Chavacano, Bisaya, Yakan, Tausug, Badjao, and Maranao ethnic groups. Christianity and Islam exist harmoniously. Isabela is 4th class city, an improvement from its 5th class city status in 2001.
Isabela City is the center of commerce, industry, and services of Basilan province. Isabela’s proximity to Zamboanga City confers tremendous advantages through economic spillovers. It now takes roughly 45 minutes to travel from Isabela City to Zamboanga due to improvements in sea transportation. Both cities benefit from each other. Isabela supplies Zamboanga with agricultural and fishery products and labor while Zamboanga provides Isabela intermediate goods necessary for its agriculture and fishery sector, other traded goods, as well as long-haul transportation services for the bigger domestic and international markets. Residents of other municipalities in Basilan and Zamboanga City come to Isabela City for employment opportunities, tourism, and trade. Within the province, Isabela City is the jump-off point of Basileños to the Zamboanga peninsula.
Political Boundaries and Land Area
The city has a total land area spanning 22,507.6790 hectares (225.076790 sq.km). Isabela has 45 barangays, 19 of which are classified as urban and 26 rural based on current PSA data.
Eight (8) barangays are located in Malamawi Island and an islet which is part of Balatanay, while the rest of the 37 barangays are in the mainland. Of the barangays in the mainland, 12 are coastal communities.
Brief History of Isabela City
Isabela is a city that is built to stand. The travails of its local history allowed Isabela to evolve from a peaceful Yakan community called Pasengen and, later, a multi-ethnic settlement Pagpasalan during the pre-Hispanic period, to what it is today.
Isabela de Basilan, as it was then called during the Spanish colonial period, was a staging area of the Corregimiento de Basilan, one of the six (6) districts of the military government in Mindanao to protect Spain’s “possessions” in the Sulu and Basilan archipelagos. Isabela de Basilan was known for its fort, Fuerte Reina Isabella Segunda. The Fort served as a naval headquarter for the Spanish fleet in the 19th century. The Spaniards used Malamawi Island to store coal as fuel for ships. To this day, Barangay Carbon in Malamawi Island serves as a reminder of Isabela City’s steam-powered naval past.
Map 2. Political Subdivisions of Isabela City
During the early American period, the entire Basilan Island was under the Municipality of Zamboanga. It continued under this regime when Zamboanga became a charted city during the Commonwealth. Isabela de Basilan was one of the three (3) districts of Basilan Island. The others were the districts of Lamitan and Maluso. Because of the perfect climate and terrain of the island, the American colonizers at the turn of the 20th century saw an opportunity to establish a plantation agriculture colony, particularly in Isabela de Basilan and Maluso. As a result, vast swathes of forest land in Basilan were converted into rubber plantations, attracting multinationals including the likes of B.F Goodrich and Menzi Corporation. Local players followed suit for copra production.
Mobility constraints posed additional administrative burden on the local residents in performing their civic duties, e.g. filing taxes in Zamboanga City. This prompted a local representative to the Congress to file a bill that sought to separate Basilan Island from the jurisdiction of Zamboanga. During those days, it took about three (3) hours to travel by ferry from the Municipality of Isabela—the new name of Isabela de Basilan—to Zamboanga. Hence, in 1948, the whole of Basilan Island was declared a city and carved out from Zamboanga City and declared as a separate City. The Municipality of Isabela was the designated seat of government of Basilan City.
Because of the sheer size of the city, a new law was issued converting Basilan into a province in 1972. The población of Municipality of Isabela became the new and much smaller Basilan City which was not administratively part of Basilan Province. The latter consisted of all barangays outside the población of the former Municipality of Isabela plus the districts of Lamitan and Maluso. Note that during those times, the size and coverage of población as well as the districts were very different from what they are at present.
A year later, Basilan City expanded to cover barangays Campong Baro, Binuangan, Tabiawan, Busay, Lanote, San Rafael, Menzi, Kumalarang, and Kabong Bata (now, Cabunbata) in addition to the población. The remaining barangays not covered by Basilan City became the new Municipality of Isabela, with Barangay Begang as its seat of government. The Municipality of Isabela itself was declared the capital of Basilan Province. The municipality of Malamawi was a separate entity consisting of Malamawi Island, Lampinigan, Manulog, Insabdahon, and its seat of government, Barangay Carbon. Insabdahon and Manulog are now called the Moro 1 and Moro 2 islets, respectively. In 1975, Basilan City was abolished. The Municipality of Isabela was reorganized, which is an aggrupation of the former Basilan City and the municipalities of Isabela and Malamawi.
It took more than two (2) decades for Municipality of Isabela to become a component city after its residents ratified Republic Act (RA) No. 9023 on April 25, 2001. The law laid out the present boundaries of the City of Isabela.
Barely seven (7) months its proclamation as city, Isabela rejected its inclusion to the Autonomous Region in Muslim Mindanao (ARMM), effectively relegating it an administrative enclave of Basilan island province. This was affirmed in 2019 when Isabela City also declined to join the new Bangsamoro Autonomous Region in Muslim Mindanao (BARMM). Under the existing arrangement, Isabela City is under the administrative jurisdiction of Zamboanga Peninsula (Region IX). Hence, all regional services are being provided for by Region IX, and provincial services are provided by Basilan.
 Department of Finance Order No. 23-08 (July 29, 2008).
 Republic Act No. 288, June 16, 1948
 Presidential Decree No. 356, December 27, 1973
 Presidential Decree No. 593, December 2, 1974
 Presidential Decree No. 840, December 11, 1975.