Introduction to the Tbilisi Underground Printing House: This printing house is well known in China because of Mr. Mao Dun's article "Tbilisi Underground Printing House". From 1904 to 1906, Stalin and other revolutionaries secretly printed revolutionary newspapers and propaganda materials here. In 1906, during a search by the Tsarist Russian police, the underground printing office was discovered and destroyed. During the Soviet period, a memorial hall was built here. Today, this is the headquarters of the United Communist Party of Georgia. Due to rising groundwater levels, the underground printing house and the printing presses inside have been flooded since 2008, making it no longer possible for tourists to visit.