The construction of Line 1 officially began on 28 December 1992. Before that, in October 1992, workers began on a trial part of the line. Many construction techniques were used when building the metro. They were new to China and included immersed tubes and tunnel boring machines. Line 1 needed ¥12.75 billion to be built and the city government of Guangzhou raised all the money. The mayor at the time, Li Ziliu wanted to use cut-and-cover tunnels. This meant that almost 100,000 people had to leave their homes and almost of buildings had to be destroyed.