For decades, commuters wishing to travel from the city's north to its east (and vice versa) have had to deal with bottom-clenching traffic jams on Lat Phrao and Srinakarin roads, two heavily congested roads which form the city's main north-east corridor. In 2005, in a bid to clear up some of the congestion, the Yellow Line was first proposed initially as a heavy underground rail service but it wasn't until 2012 that substantial plans to build it as a monorail link along the north-east corridor began to surface.