"Unlike typical travel products, our trips are not uniform and our guides are experts in their fields, such as zoology. You never know what animal you may encounter until it happens, so each experience is different."

Their peak time is summer and winter vacations, and the children taking part are 6 to 12 years old. The company also organizes short trips to museums in China and provides children with courses taught by experts about nature and wildlife.

Other companies have begun to set up travel packages around the theme of natural science, having noticed the family-travel market's potential. But there is still little in the way of regulation in this emerging sector.

"The more I learn about nature, the more I like it," Yunsong says.

"When I'm in the wilderness, I feel like I'm part of the Earth. It's good to know that there will always be this natural paradise that can comfort your heart."