The development of a major road network in Manila was first conceived in the Metropolitan Thoroughfare Plan of 1945, predicting that the metropolis would expand further to the shorelines of Laguna de Bay. The plan proposed the laying of circumferential roads 1 to 6 and radial roads 1 to 10.[2]
Between its northern terminus at the Manila North Harbor and Mendiola Street, C-1 is known as Recto Avenue. It begins at the intersection with Mel Lopez Boulevard (R-10) at the border between Tondo and San Nicolas and runs the entire length of Recto Avenue, passing through Binondo, Santa Cruz, Quiapo, and Sampaloc up to the intersection with Mendiola Street and Legarda Street (R-6). LRT Line 2 currently runs above the avenue eastwards from Alonzo Street.
C-1 then merges with Nepomuceno Street briefly until it meets P. Casal Street at the intersection with Arlegui Street.
P. Casal Street
Between Arlegui Street and Ayala Bridge, which crosses the Pasig River and Isla de Convalecencia, C-1 is known as P. Casal Street. It passes the Technological Institute of the Philippines campus in Quiapo and enters San Miguel after crossing the Estero de San Miguel. It intersects with General Solano Street and Carlos Palanca Sr. Street, which provides access to the Malacañang Palace complex and the commercial area of Quiapo, respectively, before reaching the Ayala Bridge.