Su'ao-Hualien Highway

Suhua Highway, also called Suao-Hualien Highway, is a 118-kilometre section of the Provincial Highway No. 9 in Taiwan, starting at Su-ao Township, Yilan and ending at Hualien City, Hualien. With a portion built alongside very steep cliffs high above the Pacific Ocean, it is a dangerous yet scenic drive. Famous tourist stops include the Chingshui Cliffs.

A footpath between Su-ao and Hualien was first built by the Qing Chinese government between 1874 and 1876, as part of a program to assert its sovereignty over eastern Taiwan – hitherto inhabited mostly by Taiwanese aborigines – after the Taiwan Expedition of 1874 by Japan. The narrowness of the footpath, dictated by the extreme cliffside topography, meant that its military value far outweighed its economic benefit, and it was subsequently abandoned and rebuilt several times. Eventually it was widened by the Japanese colonial government; with 9 bridges built, 14 tunnels constructed, and road surface covered with gravel, the highway was opened to vehicular traffic in May 1932.

Nonetheless the northern portion of the highway, between Su-ao and Taroko, was just 3.56 metres in width, permitting only one-way traffic at a time. Vehicles were required to travel in convoys, controlled by six "passing loops" along the route. With no guard rails to speak of, and with falling rocks a constant threat, the cliffside highway was regarded as one of the most dangerous in the world. Nonetheless it remained the main transport link between eastern and northern Taiwan, until the completion of the North-Link Line railway in 1980.

Finally in the 1980s the northern portion of the highway was widened again to facilitate two-way traffic; construction was completed in 1990.

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Wikipedia