In China, historic buildings are picked up and moved when they're in the way of urban development.

The imposing Zhangfei Temple in China today overlooks a beautiful section of the Yangtze River. But when this elaborate building was first built during the Song dynasty (960 to 1279) -- it was rebuilt in the same place in 1870 after a major flood -- it had a different view completely.

Commemorating legendary military leader Zhang Fei, who lived during the tumultuous Three Kingdoms period, the temple was originally erected in Yunyang, Chongqing province, on a steep hillside facing the river -- its design intended to integrate with the dramatic landscape.

But in 2000 it was relocated 20 miles (32 kilometers) at a cost of more than $12 million, according to state broadcaster CCTV . The temple shifted to the bottom of the Feifeng Mountain during the construction of the Three Gorges Dam, which began in 1994.

The Zhangfei Temple is by no means the only historic monument in China to have been transplanted.

The Zhangei Temple as it stands today, after being relocated to the Feifeng Mountain by the Yangtze River. Credit: Tim Zachernuk

In recent years, the practice of taking apart inconveniently located historic structures and reassembling them elsewhere has become a national specialty, with a whole industry emerging to cater to this engineering feat.

Some firms slide buildings into their new position on rails.

Others dissemble them from roof tile to foundation and rebuild them in a new continent.

A new map

Over the past half century, China's landscape has been redrawn.

Between 1995 and 2015, the urban population in China increased from 352 million to 771 million, according to the National Bureau of Statistics of China . There are now 14 cities with more than 5 million residents. And in 2016 alone, China built 84 skyscrapers, according to the Council on Tall Buildings and Urban Habitat

As aggressive urbanization swept the nation, tens of thousands of historic sites were lost. Relocation became a preferable alternative to demolition -- and there was precedent for it.

In 1964, the ancient Abu Simbel temples in Egypt, which had stood for more than 3,200 years, had been relocated 656 feet (200 meters) to make way for the construction of the Aswan Dam.

The Abu Simbel, which is located 497 miles (800 kilometers) south of Cairo in Egypt, consists of two rock temples. Credit: KHALED DESOUKI/AFP/AFP/Getty Images

That project paved the way for other nations, such as China, to rejig their cultural landscape, Hoyin Lee, associate professor in architectural conservation at the University of Hong Kong, tells CNN.

"(The move in Egypt) led some people to think that relocation is okay. But we're talking about irreplaceable artifacts," Lee says.

New millennium

China started moving monuments on a noticeable scale "at the turn of the millennium", according to Lee.

In 2001, the Jinlun Guild Assembly Hall, in the southern megacity of Guangzhou, was one of the first structures to be completely relocated in China. Built in the early 1700s, during the Qing Dynasty, it was moved 264 feet (80.4 meters) to enable the construction of Kangwang Road, to link the northern and southern areas of Liwan District.

In 2003, the Shanghai Concert Hall experienced a similar fate. Built in 1930, it was moved to make way for the construction of Yan'an Elevated Road.

First, the building was raised 5 feet (1.4 meters), placed on a pre-made track and slid 218 feet (66.4 meters). Then it was again raised by 6 feet (1.88 meters), while a new foundation for the building was constructed under it.

The 78-year-old six-storey Zhengguanghe Building made history as the heaviest structure ever moved. Credit: Jiang ren/Imaginechina/AP

Meanwhile, Zhengguanghe Building, a six-story warehouse in Shanghai, in 2013 -- designed by British architect George Wilson and constructed in the 1930s -- was shifted 125 feet (38 meters) to accommodate local redevelopment.

And the Hankou Yiyong Fire Association, a building erected by local firefighting volunteers some 100 years ago and which is classed as a historic site in Wuhan, Hubei province, made news in 2011 when it slid 295 feet (90 meters) on a set of rails.

The three-story Hankou Yiyong Fire Association building underwent a monolithic move in 2016, sliding across a set of rails. Credit: VCG/Getty Images

The land it was located on had been purchased by real estate developers, according to the China Construction Engineering Management Association.

"China is going through a time of major development and people are feeling a conflict between preserving historical buildings and achieving economic growth," Tang Guo-wah, a professor at Guangzhou University's School of Architecture and Urban Planning, tells CNN.

"(As a result) we are seeing the incorrect handling of structures like tearing them down, or relocating them."

A slice of history

One of China's most dramatic relocation projects spanned two continents.

With its beautiful carved-brick exteriors and grand reception halls, Yin Yu Tang was a typical 18th century ancestral home of a Chinese merchant family.

But this property, which was built in Huizhou, in Anhui province, was transplanted in the late 1990s to the Peabody Essex Museum (PEM) in Salem, Massachusetts, in a massive logistical feat.

Nancy Berliner, now a curator of Chinese art at the Museum of Fine Arts, Boston, came across Yin Yu Tang in Anhui while working with the PEM and researching Chinese vernacular architecture and furniture in 1996.

"A neighbor opened the doors for me to peek in," she tells CNN, and it transpired that the family who owned it were looking to sell the property.

The PEM acquired the house for an undisclosed sum.

"Had the house not come to the PEM, it most likely would have been sold for its parts," Berliner tells CNN. "The wood and bricks would have gone to other local people's building projects, and some of the carved wooden decorative elements might have been sold in antique shops for decoration.

"In some cases, relocation can help to preserve heritage."









1 / 5 – Yin Yu Tang Yin Yu Tang was moved from Huizhou, in Anhui province, to the Peabody Essex Museum (PEM) in Salem, Massachusetts, in the late 1990s. Credit: 2008 Peabody Essex Museum, Salem, MA/Dennis Helmar

Architectural drawings, measurements and photographs were taken before the "slow and careful dismantling of the house", from the roof tiles down to foundation stones. It was packaged up and shipped to the US.

During the dismantling of mortise-and-tenon joints, original calligraphy notations and small amulets and coins were found between the wooden components.

"The relocation of Yin Yu Tang was a rare opportunity to literally dissect a work of architecture," Berliner says. "So often, we only see the surface of a building, but in dismantling the house we were able to learn about many aspects of how the house was constructed."

A whole industry

So how exactly is a building moved?

"Before a building is lifted, both upper and lower trays (to support the building) are installed, to 'package' the construction and prepare it for the move," Lan Wuji, founder of Shanghai-based Evolution Shift , a company that specializes in building relocation, tells CNN.

"There are different approaches to the move itself. Sometimes (the building) slides -- in which case a set of rails need to be built -- and sometimes the structure is pulled by truck-like vehicles," he says.

Evolution Shift has undertaken high-profile relocations such as the old British Embassy in Beijing (moved in the early 2000s), and the now-defunct Agricultural and Industrial Bank of China, which moved 164 feet (50 meters) in 2008 to make way for the construction of the National People's Congress office in the capital.

Lan says half of the relocations his firm handles are of historical sites. He oversaw the relocation of the Shanghai Concert Hall, before founding his own company in 2004.

"Relocation has several benefits compared to demolition and rebuilding," Lan tells CNN. "It costs less, it provides a better conservation of the building, it's more environmentally friendly, and it saves time."

"Thanks to rapid urban development, China is a leading country in building relocation," he says, adding that there are dozens of structure relocation companies across the country.

Lan adds that it's "hard to say" how much it costs to relocate a building, since expenses vary hugely between projects.

But the Shanghai Concert Hall, which weighs 5,650 tons, cost $1.3 million to relocate.

Relocation, relocation, relocation

While most experts CNN spoke to agreed that relocation is a preferable choice to demolition they warned that a building's heritage is often bound to its location.

Built in 1844 as quarters for military officers, Murray House in Hong Kong -- a special administrative region of China -- was famously deconstructed in 1982, then relocated. Originally standing in what is now the heart of the city's financial district -- where the Bank of China's headquarters are today -- it was dismantled and kept in storage.

Murray House in Hong Kong was taken apart, then reassembled -- reincarnating as a structure by the waterfront. Credit: lamlam/Imaginechina/AP

In 2002, Murray House was unveiled in its new location of Stanley, a beachfront neighborhood about 9 miles (15 kilometers) away. The structure is now a dining and shopping complex, nestled by the waterfront.

"Hundreds of years later, you're going to have people wondering, 'Why is this building here?'" Lee says, adding that "there are no benefits (to relocation) whatsoever".

"It completely destroys (the structure's) original intentions."

Queen's Pier in Hong Kong was controversially demolished in 2007 to make way for the construction of a major highway. Its parts are in storage and there are calls for it to be reassembled. Credit: MIKE CLARKE/AFP/Getty Images

Berliner herself agrees that relocation isn't always a good thing.

"In any country when there is no choice but to take down a historical monument, relocation is certainly better than destruction. However, finding other solutions so that the monument can stay in its original context is ideal."

No more movement?

As the pace of China's economic growth begins to slow , and urbanization as a result loses momentum, there are signs that attitudes towards preserving historic buildings are changing.

It's been a long time coming.

In 2002, the State Administration of Cultural Heritage (SACH) drew up the Principles for the Conservation of Heritage Sites in China (the "China Principles") -- which state that "intervention to a heritage site should be restricted to the minimum necessary to ensure its preservation" -- but these guidelines were not legally binding.

While they could have been enforced through China's heritage conservation law -- the Law of the People's Republic of China on Protection of Cultural Relics which directly addresses the relocation of "immovable cultural relics" -- too often this simply didn't happen.

“ Any transplantation and business for historic structures in China will be strictly controlled, and happen less and less. ” Chang Qing, Tongji University Department of Architecture

However, in 2015 the government released "An Emergency Notice on Firmly Banning the Relocation of Traditional Buildings, and Following the Laws Against Theft of Components" -- which seemed to signal a tougher stance.

"The (emergency) notice was not a law, but a clarification of the enforcement of existing laws to prevent the illegal demolition and 'theft' of cultural heritage properties -- as in, selling whole buildings or decorative parts to private collectors and overseas museums," Lee tells CNN.

The notice reinforces rules against structure relocation in light of an increase in damages to cultural relics, though enforcement at a local level could still prove to be a complicated matter.

"For national monuments, it's easier to enforce protection and conservation because they have the national government's attention; for anything less, it's really up to the local government," Lee adds.

"Local governments' behavior in heritage (protection) is bound by the conservation law," Chang Qing, the head of Tongji University's Department of Architecture, tells CNN. "Any transplantation and business (in relation to) historic structures in China will be strictly controlled, and happening less and less."

But perhaps the strongest signal of change came at the end of 2016, when the Chinese Society of Cultural Relics and the Architectural Society of China published its 20th Century Chinese Architectural Heritage List, which named 98 buildings worthy of preservation.

The People's Hero cenotaph, in Beijing, made the government's 20th Century Chinese Architectural Heritage List. Credit: STR/AFP/AFP/Getty Images

The list featured iconic landmarks such as the Monument to the People's Heroes cenotaph in Beijing, and Western-style structures including Saint Sofia Cathedral in the northernmost province of Heilongjiang. The buildings were chosen for both their significance in Chinese history and architectural mastery.

While the list doesn't provide any legal protection to the buildings it shows the government is thinking about architectural heritage.

Prosperous times

Over the past decade, following constant calls for protection by experts, China has started to understand the value of historic monuments, Tang says.

"There's an old Chinese proverb: 'In prosperous times, cultural relics are repaired'. You only get to repair cultural relics when you have money."

"When economic development reaches a certain stage, it's only then that people turn around and say: 'What have we lost? Where are our memories?'"