Answer the following question: Information: - The Seoul Metropolitan Subway is an integrated urban rail transit system consisting of 20 rapid transit, light metro, commuter rail and people mover lines located in South Korea. The system serves most of the Seoul Metropolitan Area including the Incheon metropolis and satellite cities in Gyeonggi province. Some lines in the network cross large rural areas to reach major cities in northern Chungnam province and western Gangwon province that lie over 100km away from the capital. - Gyeongju, historically known as "Seorabeol", is a coastal city in the far southeastern corner of North Gyeongsang Province in South Korea. It is the second largest city by area in the province after Andong, covering with a population of 264,091 people (as of December 2012.) Gyeongju is southeast of Seoul, and east of Daegu. The city borders Cheongdo and Yeongcheon to the west, Ulsan to the south and Pohang to the north, while to the east lies the coast of the East Sea. Numerous low mountainsoutliers of the Taebaek rangeare scattered around the city. - The Jungang Line (literally "Central Line") is a railway line connecting Cheongnyangni in Seoul to Gyeongju in South Korea, traversing central South Korea from the northwest to the southeast. It also referred to the rail line of the Seoul Metropolitan Subway from Yongsan Station to Yongmun Station. - Guksu Station is a station on the Jungang Line , located in the county of Yangpyeong . The station used to be the eastern terminus of Jungang Line . The line now extends further to Yongmun Station to the east . - South Korea, officially the Republic of Korea (ROK), is a sovereign state in East Asia, constituting the southern part of the Korean Peninsula. - Yongsan Station is a major railway station in Seoul, South Korea. It is located in Yongsan District, and adjoins the Yongsan Electronics Market. The station is the terminus for high-speed and long-distance trains on a number of railway lines, including most trains on the Honam Line, its high-speed counterpart, and all trains on the Janghang and Jeolla Lines. What is the relationship between 'guksu station' and 'railway station'?
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