Wu Gorge is the most beautiful section of the Yangtze River, flanked by high peaks that are often capped by fog or clouds. The steep slopes of the gorge are green with trees and bushes. The gorge was long known to be as dangerous as it is beautiful. It was a dangerous place for boat navigators, who faced dangers including whirlpools, quicksand, and currents that varied from hour to hour. As the river cuts its way through the Wushan mountains, its roaring currents change their directions constantly. Wu Gorge is 45 kilometers (28 miles) long, extending from the mouth of the Daning River in the west to the north-bank town of Guangukou, in Badong County, in the east. The small trading town of Peishi marks the provincial border, where the river crosses from Sichuan Province into Hubei Province. The gorge is divided into two main sections, the Golden Helmet and Silver Armour Gorge and the aptly-named Iron Coffin Gorge. Wushan, a town that is well known for its extraordinarily beautiful setting, looks both down the Wu Gorge and up the Daning River into the Three Little Gorges.