Major rivers flowing through the municipality, including the Chaobai, Yongding, Juma, are all tributaries in the Hai River system, and flow in a southeasterly direction. The Miyun Reservoir, on the upper reaches of the Chaobai River, is the largest reservoir within the municipality. Beijing is also the northern terminus of the Grand Canal to Hangzhou, which was built over 1,400 years ago as a transportation route, and the South–North Water Transfer Project, constructed in the past decade to bring water from the Yangtze River basin.