These are some of the photos Gao Yuan has taken for tourists. [Photo/VCG]

Gao also remembered a blind homeless man. The man walked his bike with all his belongings on it. The first time the man came, he pinned a piece of cloth written with the date near his right shoulder for the picture. He paid Gao in small currency notes. The man came for another photograph this year, but Gao didn't charge him this time.

Gao also recalled an older couple who every year came to get their photos taken at the same spot for 16 years.

Then there was the couple from Southwest China's Yunnan province celebrating their 50th wedding anniversary, who got their picture taken while holding their old-time marriage certificate.

"I feel honored to record these moments for people. I would love to come and take photos for them for free next time they come, even if I am retired," said Gao.