The road starts at the Tagaytay Rotonda, a four-way roundabout with Aguinaldo Highway, Tagaytay-Nasugbu Highway, and Tagaytay-Talisay Road in Tagaytay City. Various restaurants, hotels, residential developments, and tourists attractions could be found along this road. It then intersects the Santa Rosa-Tagaytay Road, which provides access to the South Luzon Expressway and Ligaya Drive, where N421 turns and the road transitions from a secondary road to a tertiary road. It then climbs Mount Sungay and terminates at the People's Park in the Sky. The entire Tagaytay segment is also known as Isaac O. Tolentino Avenue.