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The MacArthur Highway, officially the Manila North Road (MNR or MaNor), is a 685-kilometer (426 mi), two-to-six lane, national primary highway and tertiary highway in Luzon, Philippines, connecting Caloocan in Metro Manila to Aparri in Cagayan at the north. It is the second longest road in the Philippines, after the Pan-Philippine Highway. It is primarily known as MacArthur Highway in segments from Caloocan to Urdaneta, Pangasinan, although it is also applied up to Ilocos Sur and called Manila North Road for the entire length.
Manila North Road's section from Caloocan to Urdaneta, Pangasinan is officially recognized as MacArthur Highway, although it is also known as such in La Union and Ilocos Sur. Its section that forms part of N1/AH26 from Laoag to Aparri is also known as Maharlika Highway and part of Laoag–Allacapan Road.
Through the city proper of San Fernando, La Union, the road is locally known as Quezon Avenue. In Laoag, it forms part of Laoag–Paoay Road between Laoag Airport Road and at the city proper, it is locally known as J.P. Rizal Avenue and Gen. Segundo Avenue, respectively.
History
The highway was built in sections beginning in 1928 during the American colonial period. It followed much of the route of the old Manila Railroad line from Manila to Dagupan. It was designated Highway 3 or Route 3 in early U.S. military records. It also reached south up to Manila through the present-day alignment of Rizal Avenue (Route 3A); the highway's section from Caloocan to Valenzuela (formerly Polo) was once part of Rizal Avenue Extension. However, Highway 3 had different alignments: in Valenzuela, it used a route still existing today in barangay Malanday; in Bulacan, it went along the Maharlika Highway and Pulilan Regional Road from Guiguinto to Calumpit via Pulilan; in San Fernando and Angeles, Pampanga, it is known as the Old Manila North Road; and in Paniqui, Tarlac, it followed Paniqui Poblacion Road. New alignments were eventually developed, forming the present-day Manila North Road, which, by the 1950s, extended to Aparri in Cagayan, incorporating the former Cagayan–Ilocos Norte Road.
On June 17, 1961, the section of the Manila North Road from Caloocan to Urdaneta, alongside the western road that leads to Lingayen, was renamed MacArthur Highway in honor of the Liberator of the Philippines during World War II, General Douglas MacArthur.