GRAND CANAL

Italian Canale Grande, main waterway of Venice, Italy, following a natural channel that traces a reverse S-course from St. Mark's Basilica to Santa Chiara Church and divides the city into two parts. Slightly more than 2 miles (3 km) long and between 100 and 225 feet (30 and 70 m) wide, it has an average depth of 17 feet (5 m) and connects at various points with a maze of smaller canals. These waterways carry the bulk of Venetian transportation by traditional gondolas and now mainly by motorboats and small steamers (vaporetti). The Grand Canal is lined on either side by palaces, churches, hotels, and other public buildings in Romanesque, Gothic, and Renaissance styles and is bridged at three points (at about the midpoint by the famous Rialto Bridge). Cargo barges on the Grand Canal at Suchow, Kiangsu province. Wade-Giles romanization Ta Yn-ho, Pinyin Da Yunhe, series of waterways in North China that link Hang-chou in Chekiang province with Peking. Some 1,085 miles (1,747 km) in length, it is the world's longest man-made waterway, though not all of it is, strictly speaking, a canal. It was built to enable successive Chinese regimes to transport surplus grain from the agriculturally rich, relatively underpopulated Yangtze and Huai river valleys to feed the capital cities and large standing armies in North China. The oldest part of the canal lies between the Yangtze and the city of Huai-yin (also called Ch'ing-chiang; in Kiangsu province), which was originally on the Huang Ho (Yellow River) when that river had a far more southerly course. This section, traditionally known as the Shan-yang Canal, in recent centuries has been called the Southern Grand Canal (Nan Yn-ho). This ancient waterway was possibly constructed as early as the 4th century BC, was rebuilt in AD 607, and has been used ever since. The Sui dynasty (581-618) built the first great canal system in 607-610, constructing a northeast-southwest link from the Huang Ho (when the Huang had a northern course) to the Huai River. Known as the New Pien Canal, it remained the chief waterway throughout the T'ang period (618-907) and in the early Sung period (960-1126). The need for a major transport link again arose under the Yan (Mongol) dynasty (1279-1368), whose capital at Peking required a grain-supply system. In 1282-83 it was therefore decided to build a new canal from the Huang Ho-which since 1195 had changed its course southward to usurp the former mouth of the Huai below Huai-yin-to the Ta-ch'ing River in northern Shantung province, which was dredged to give an outlet to the sea. The mouth of the Ta-ch'ing, however, silted up almost immediately. An alternative canal, cut across the neck of the Shantung Peninsula from the harbour of Tsingtao to I-hsien, also proved impracticable and was abandoned. Eventually another stretch of canal, the Hui-t'ung Canal, was built to join Tung-a-chen on the Huang Ho with the Wei River at Lin-ch'ing. In this way, the modern Grand Canal came into being. During the Yan period, however, canal transport was expensive and inefficient, and most grain went by sea. At the beginning of the Ming dynasty (1368-1644), the capital was at Nanking. After Peking again became the seat of government in 1403, the whole canal-including the section from Lin-ch'ing on the Wei to its junction with the Huang Ho, which was dredged and repaired-remained in operation until the 19th century. It comprised six main sections: (1) a short canal from the outskirts of Peking to T'ung-chou, (2) a canalized river joining the Hai River to Tientsin and then joining the Wei River as far as Lin-ch'ing, (3) a section in Shantung rising over comparatively high ground from Lin-ch'ing to its highest point near Chi-ning and then falling again to a point near Schow, a difficult stretch with a number of sluices and dams using water from a number of small rivers flowing off the T'ai Mountains and from the string of lakes southeast of Chi-ning, (4) a stretch from Schow that followed the southern course of the Huang Ho as far as Huai-yin, (5) a section from Huai-yin following the ancient Shan-yang Canal south to Chen-chiang on the Yangtze, and (6) a section south of the Yangtze where the canal, there called the Chiang-nan Yn-ho, ran southeast then southwest for some 200 miles (320 km) via Su-chou to Hang-chou. In the 19th century a series of disastrous floods broke the dikes of the Huang Ho (which began to move to its present northern course), caused great problems in the section of the canal between Schow and Huai-yin, and cut across the canal between Lin-ch'ing and Chi-ning. After the Taiping Rebellion (1850-64) and the Nien Rebellion (1853-68), the use of the canal as the major supply line to Peking was abandoned, and the canal gradually fell into disrepair in its northern sections. After 1934 the Chinese Nationalist government carried out extensive works on the canal between Huai-yin and the Yangtze; ship locks were constructed to allow medium-sized steamers to use this section, which was dredged and largely rebuilt. New work was begun under communist rule in 1958 to restore the whole system as a trunk waterway able to carry ships of up to 600 tons. Between 1958 and 1964 it was straightened, widened, and dredged, one new section 40 miles (64 km) long was constructed, and modern locks were added. The canal can now accommodate medium-sized barge traffic throughout its length. The main traffic, however, is concentrated in the southern half. The canal is also used to divert water from the Yangtze River to northern Kiangsu province for irrigation, making possible double cropping of rice.