The Five Generations of National Gates in Manzhouli.

Manzhouli is located to the north of Russia and to the west of Mongolia. It is an important port for China to Russia. Historically, five national gates have been established, known as the Five Generations of National Gates. The First Generation of National Gate (Figure 2): Built around 1902. This is the initial boundary marker between China and Russia, consisting of wooden stakes, marking the border between the two countries. The Second Generation of National Gate (Figure 3): Built in 1920. This is a wooden arch structure, with "China-Soviet Gate" written in Chinese on the Chinese side. The Third Generation of National Gate (Figure 4): Built in 1968. This is a "gate"-shaped trestle bridge across the railway, with the red slogan "Workers of the World, Unite" embedded on it. The Fourth Generation of National Gate (Figure 5): Built in 1989. This national gate is solemn and majestic, 12.8 meters high and 24.45 meters wide, and is a national gate in the true sense. The Fifth Generation of National Gate (Figure 6): Built in 2008. This national gate is the largest railway port on the Chinese border, with a total length of 105 meters, a width of 46.6 meters, and a height of 43.7 meters. These national gates not only witnessed the historical changes of Manzhouli as an important port for Sino-Russian trade, but also reflected the development of Sino-Russian relations.