A 7.8-kilometer-long trunk highway tunnel designed to cross Taihu Lake has cast its first roof concrete in Jiangsu Province. The tunnel, as part of the provincial highway 341, links Mashan and Zhoutie, both towns in Jiangsu's Wuxi City, with a shortcut under one of the largest freshwater lakes in China. The roof concrete is 1.4 meters thick and 20 meters long, covering nearly 1,200 square meters, or about three standard basketball courts. After completion, the highway tunnel can boost the domestic economy along the route and facilitate the development of local tourism.