Sanghai, China. An 85-year-old primary school in Huangpu district, Shanghai was lifted off the ground and moved 62 meters to a new location using a new technology called the “walking machine.”

In an effort to preserve the city’s historic structures, engineers moved the five-story 7,600-ton building attaching 198 mobile supports under it, which acted like robotic legs.

They’re split into two groups which alternately rise up and down, imitating the human stride. Attached sensors help control how the building moves forward, said Lan Wuji, chief technical supervisor of the project.

Workers had to first dig around the building to install the 198 mobile supports in the spaces underneath, Lan explained. The robotic “legs” were then extended upward, lifting the building before moving forward.

Relocating the Lagena Primary School was different from standard building relocation efforts as other square or rectangular structures would be moved using rails or vehicles, but the school’s irregular T-shape posed a unique challenge. Moreover, the building had to be moved 203 feet in a curved direction and not a straight line. Experts, hence, decided to chose the “walking machine” technology.

By the time the relocation completed on October 15, it had taken 18 days for the building to be rotated 21 degrees and moved 62 meters away.

The school building constructed in 1935 was moved in order to make space for a new commercial and office complex, which will be completed by 2023.The building is being converted into a centre for heritage protection and cultural education, CNN said.