Cao Wei works as a guide at Qinglongqiao Railway Station, a historic station of Jingbao Railway located in Beijing. [Photo by Zuo Xifeng/For China Daily]

On summer nights, young Cao would hear the elders talk about these things.

"Although I could not understand these things, the chats broadened my view of the world, and influenced my life," says Cao says, adding "that's why the popularization of scientific knowledge is so important".

Meanwhile, in 2015, Cao's company started hosting an annual photography contest.

This contest does not focus on photography skills, but Cao takes participants to 10 museums to shoot pictures that showcase the progresses of science and technology through the relics.

One of the winner in 2015 took the picture of pottery cup from early human history.

The red pottery cup was found in Jiangxi province in 1962, and after tests in China and the United States in 2012, the cup was dated to about 20,000 years ago, marking the turn of human history from the Paleolithic Age to the Neolithic Age.

Speaking about the contest, Cao says: "What we want to show through discovering science and technology in cultural relics is how humans accumulate wisdom."