Zhou Yihan reaches Xuwen county, Guangdong province, the northern side of the Qiongzhou Strait, after swimming for 13 hours. [Photo provided to chinadaily.com.cn]

Zhou suffered from swollen lips, hands and feet after she was stung by jellyfish like some other swimmers.

Her father, who swam across the strait last year, helped drive away jellyfish in the water. Her coach also swam for some time to encourage her to overcome the influence of the jellyfish.

The girl also encountered backwash flows, rain, high waves and lightning, shifting from freestyle to breaststroke sometimes to relieve fatigue and relax muscles.