Shenzhen's Guomao Building contains special memories for many, including Wang Shungao and his family.

The iconic skyscraper in Shenzhen, once the tallest in China at 160 meters, was also known for the speed of its construction from 1983 to 1985, with a notable record of "building one floor in just three days."

Wang came to Shenzhen four decades ago to participate in the construction of the building and decided to stay. Having witnessed how the city has developed, he said he's proud of his contribution.

This month Shenzhen will mark 40 years since being designated as China's first Special Economic Zone. The historic decision has transformed the city into a model economy not only for other parts of the country, but for other regions around the world. 

"When we were building Guomao, the only high-rise was a mall near us. As we went taller than the mall, we got excited. Then we made it even taller, and we could see Hong Kong behind the mountains," Wang said.

Wang said he had not only given his toil and sweat, but also fell in love on the job where he met his wife Du Xianfang, a construction colleague at the time.

According to the couple, the biggest motivation of workers back then was to help their country get on the fast track of development.

"We simply thought that this was a project that carried the hopes of people around the country. We felt we should do it well, do it fast, and be worthy of their trust," Du said.

The couple's dream continues, as their daughter Wang Qianqian has also chosen construction and aims to emulate her parents.

"The society is developing fast," Qianqian said. "I want to do a better job and I feel a lot of pressure."

The construction process has advanced significantly since Guomao was built but the skyscraper remains a trailblazer that encourages the young generation in Shenzhen to carry on the city's legacy.