The O-Train derives its name from the word "One," as the three provinces (Gangwon-do, Chungcheongbuk-do, Gyeongsangbuk-do) in the country's central inland region are connected by this one circular route. The train was designed with the theme of the four picturesque seasons of Baekdudaegan, Korea's biggest and longest mountain range that stretches from Baekdusan Mountain to Jirisan Mountain. The four-cabin train carries up to 205 people and includes separate seating options for families and couples to accommodate the needs of different passengers. There are also individual observatory seats for people traveling on their own. The train is well-equipped with various convenience facilities including a café, children's play area, toilets, etc. The train moves at the 165km per hour of speed, allowing passengers to reach Seoul to inland region quicker and easier than before. The exterior of the train is decorated with the pictures representing the beautiful scenery of Korea's four seasons, whereas the insides are dotted with highlights taken from Baekdudaegan mountain range.