In early December, Liu Zhangning was tending her cabbage patch when she saw a tall yellow construction crane in the distance. At night, the work lights made it seem like day.
Fifteen days later, a 30-story hotel towered over her village on the outskirts of the city like a glass and steel obelisk.
"I couldn't really believe it," Liu said. "They built that thing in under a month."
A time-lapse video of the project in Changsha, which shows the prefabricated building being assembled on site, has racked up more than 5 million views on YouTube and left Western architects speechless.
"I've never seen a project go up this fast," said Ryan Smith, an expert on prefabricated architecture at the University of Utah.
In other countries, the most advanced prefab construction methods can reduce building times by a third to half, Smith said. The builders of the Changsha hotel did better, knocking one-half to two-thirds off the normal schedule.
"It's unfathomable," Smith said.
The warp-speed construction is a startling illustration of the building boom in China, where an exodus from the countryside to the cities has swelled the urban population by almost 400 million since 1990.