Passenger surveys in the first months found that the limited capacity of bus connections and the lack of subway connections for intermediate stations, especially the newly built stations Gwangmyeong and Cheonan-Asan, was the problem mentioned most often. A better connection to Cheonan-Asan Station was provided by an extension of Seoul Subway Line 1 along the Janghang Line, opened on December 14, 2008. Gwangmyeong Station was linked to the same subway line by a shuttle service on December 15, 2006, but it made little impact due to the longtime differences between KTX and subway train schedules.