Blue Line (RTS Koiwai)

The Blue Line of the RTS Koiwai consists of 7 rapid transit stations from Summerfield to Finance. It exists completely within the City of Koiwai, and will travel between downtown and the national government center when RTS Koiwai's Phase IV is completed. It currently terminates at Finance Street, next to the Koiwai Stock Exchange. This was the third line for which construction began. It shares three stations with the currently under construction Purple Line.

When the Blue Line was first opened, it shared tracks with the Yellow Line from KDOT/Metro Center-Dalmasca to Elysian Fields, then switching onto its current route onto Elysian Fields Avenue before Capital Park station. In Phase III, the Blue Line was realigned to a new terminus at Summerfield station via Ivalice Boulevard. The Blue Line now utilizes a new platform at Elysian Fields station, now bisecting the Yellow Line. In Phase IV, the Blue Line will be extended from Finance to Federal Center NE, with two stops at the National Capitol, connecting with the Capitol Transitway for legislators and their staff.