National Freeway 3 (), also known as Formosa Freeway (), is a freeway in Taiwan. It is the second north–south freeway in Taiwan, beginning in Keelung City at Jijin Interchange on the provincial highway 2 (Jijin Road) and ending in Linbian, Pingtung on the provincial highway 17. It is the longest freeway in Taiwan with a total length of . The freeway is also the only one in Taiwan to have a spur route, Freeway 3A. The highway has 58 interchanges, 15 junctions, 7 service areas and 3 rest areas en route. Aside from the 58 public interchanges, there are also some interchanges reserved for governmental usage. Route Description This freeway mostly serves as a bypass to major cities in Western Taiwan, traveling through suburban and rural areas. However, Freeway 3 is also the primary freeway in the counties of Nantou and Pingtung, as well as the first ever being built in these counties. Various expressways and east-west freeways link Freeway 3 with urban areas typically served by Freeway 1. The purposes of this freeway are to increase economic development in the rural area and to relieve congestion along Freeway 1. The freeway begins at an intersection with Provincial Highway 2 () and Provincial Highway 2F () in Keelung. Highway 2F, also known as Port of Keelung Western Connector (), is an elevated road that connects the Port of Keelung with Freeway 3. The freeway travels in a northeast-southwest direction through the western part of Keelung before intersecting Freeway 1 in Xizhi. The freeway then travels along the mountains of New Taipei City and Taipei, bypassing the southeastern and southern edge of the Taipei metropolitan area. Connections to downtown Taipei are available through Huandong Blvd () in Nangang and Freeway 3A in Wenshan. In Nangang, the freeway intersects National Freeway 5, which travels through the Xueshan Range before reaching Yilan County in Eastern Taiwan. In Yingge, the freeway meets National Freeway 2 which provides connections to downtown Taoyuan as well as Taipei's main international airport, Taoyuan International Airport. In Taoyuan, the freeway is mostly parallel to Provincial Highway 3, traveling through the mountainous areas of the city. As the freeway enters Hsinchu County it turns to a slightly east-west direction before intersecting Freeway 1 for the second time at the border of Hsinchu county and Hsinchu city. This stretch of the freeway is also known as the Northern Second Freeway