The Shinbundang Line (New Bundang Line) opens today at 3pm and will run for free all day until the last train tonight.
Transfers and integrated ticket discounts will not be available until tomorrow(October 29), which is when the line officially opens for full service.
The line is more expensive than other subway lines with a standard price of 1,600 plus a 100won surcharge for each 5km after the first 10km. The reason for the high price is due to the line being built by a private enterprise.
The line is fully automated and the window at the front of the subway car is sure to be a popular spot. You can read about the line and where it can take you here.