Long proposed and supported by the NEDA-Regional Development Council-Cordillera , it as one of twelve defined metropolitan areas in the Philippines . The original " BLIST " long existed as a concept since its inception in August 1990 , a month after the 1990 earthquake which devastated the city of Baguio and other surrounding areas , and only existed as an informal reference to the area . The concept was later amended into " BLISTT " in 2009 , which included the municipality of Tublay , despite not being adjacent to the city of Baguio . It was officially established after a signing of a memorandum of agreement by the mayors of the component local government units
1990 earthquake
1990 Luzon earthquake
Metro Baguio