Line 2 (Hopo(호포)~Seo-myeon(서면)) first began operation in 1999, and the entire route (Jangsan(장산)~Hopo(호포)) was completed in 2002. Line 2 was built to solve chronic heavy traffic from east to west of the city. In 2008, the extension route (Hopo(호포)~Yangsan(양산)) was launched for developing transportation system between Busan and Yangsan city. The whole line 2 is 45.2 km in length, 43 stations. It is middle-sized subway and a 6-cars train. Shield construction method was used to build line 2. It was the first time to use this method when constructing the subway line in the country. This method was needed to build the line across Suyeong River.