Cagayan Valley Road

The road's Junction Aparri Airport–Port section starts as Loriga Gallarza Street at the Aparri Port in the northern coastal town of Aparri that also serves ferries to Batanes. It traverses the town proper and turns south as De Rivera Street. At the intersection with Rizal Street (Aparri Airport Road), N103 ends and the route number changes to N101, which it continues from the intersecting road. There, the road's Magapit–Aparri Road section commences. It then traverses the towns of Camalaniugan and Lal-lo.[3]

At the Magapit Interchange in Lal-lo, the road's route number transitions from N101 to AH26/N1 with the name Pan-Philippine Highway or Maharlika Highway as it continues its course to the south. It then traverses the towns of Gattaran, Alcala, Amulung, and Iguig. It enters the city of Tuguegarao, where it turns to the east at its intersection with Cagayan–Apayao Road/R. Balzain Highway (N51) and Tuguegarao Diversion Road II (N106). It then serves as an eastern radial road out of Tuguegarao as it diverts away from the city proper. Past Enrile Boulevard (N104), it enters the town of Peñablanca but turns away from the town proper as it would cross the Pinancauanan River back to Tuguegarao. It ends near the Cagayan–Isabela provincial boundary, where it continues as the Maharlika Highway, although the name is alternatively used up to its section in the Central Luzon province of Bulacan.[3]