Highway system in Taiwan

Highways in Taiwan are classified into five types:

The system does not apply to other parts of the Republic of China (ROC), namely Kinmen and Lienchiang counties, and islands in the South China Sea.

As a general rule, the odd numbers represent north-south highways and even numbers represent east-west. The numbers increase moving west to east and north to south. Major north-south provincial highways are indicated by a one-digit number. Special routes of a highway use the same number, followed by a heavenly stem character. However, for English translation, these characters are replaced by letters in the alphabetical order.

National highways are freeways. Their design is heavily based on the Interstate Highway System of the United States.

The older ground level National Route 1 in Taipei

National highway number

The newer upper level National Route 1 viaduct in Taipei

Exit 17 to Freeway Route 2

The first controlled-access highway, and a predecessor to the national highways in Taiwan, was the MacArthur Thruway, built in 1964 between Keelung and Taipei. Construction on the first modern national highway, National Highway 1 began in 1971. The northern section between Keelung and Zhongli was completed in 1974, and the entire freeway was completed in 1978. It runs from the northern harbor city of Keelung to the southern harbor city of Kaohsiung, while there was an 8.6-kilometre (5.3 mi) branch (No. 1A) connecting to Chiang Kai-shek International Airport (now Taiwan Taoyuan International Airport).

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