"Since the other seven sites were considered less famous and precious, they were destroyed in the past decade's process of urbanization," said Zhang.

Bringing old cities into modernity often presents city planners and officials with a dilemma about protecting the old while building up the new.

He Desai, a local historian, said that historical sites in China need to be well preserved and that demolition is usually blamed for these sites' being destroyed or disappearing.

Luo Shuwei, a member of the Society of Chinese History, said that Tianjin is a place for people in modern China to have a taste of western culture and historical stories. They can tour sites with unique architectural features and historical value.

In 2005, Tianjin issued a local regulation for the preservation of historical sites. In the following five years, the city placed 746 historical buildings under legal protection.

"Historic legacies can not be duplicated. An ideal solution is to protect whole blocks containing clusters of old buildings, and any change to them must be prudent," said Xu Subin, a professor with the School of Architecture of Tianjin University.

"Protecting the 1911 Revolution sites means a lot for both Chinese history and the younger generation," said Zhang Shaozu. "I hope the four sites can last until we celebrate the 150th anniversary of the revolution."