Dhaka, Aug. 14 -- As heatwaves sweep across China during the summer, the country's southwestern karst regions are turning their naturally cool caves into unconventional tourist attractions, offering visitors a respite from the heat while creating new business opportunities.

Guided by a local expert, tourist Chang Ting recently entered a natural cave in Guizhou Province. After walking about 100 metres along a narrow, rocky passage, she lost mobile phone reception.

"It felt like stepping into a crack in time, and all the noise faded away," said Chang, who is from Xi'an, capital of northwestern Shaanxi Province.

Cave exploration has emerged as a new summer tourism trend among young Chinese travellers. The growing interest is providing vis...