Photo taken with an UAV drone shows participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019. (Photos: Xinhua)

Photo taken with an UAV drone shows participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Photo taken with an UAV drone shows participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Photo taken with an UAV drone shows participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Photo taken with an UAV drone shows participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Participants pose for photos on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

A participant poses on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Participants pose for photos on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

A participant takes photo on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.

Participants walk on the ice-covered trekking route during an ice trekking event in Panjin, northeast China's Liaoning Province, on Jan. 26, 2019.