Aerial photo taken on May 4, 2019 shows tourists walking on a glass bridge at the Huaxi World Adventure Park in Huaxi Village of Jiangyin City, east China's Jiangsu Province. The 518-meter-long glass bridge hangs more than 100 meters above ground level at the park. It is made of panes of 35-mm-thick glass. Each glass can hold a maximum weight of 4.7 tonnes. Around 2,600 people can cross the bridge at a time. (Xinhua/Xu Congjun)