The shortest individual stretch on the SuIn line which can still be found is the short part of the line within Suwon city between the main railway line and the Deogyeongdaero (덕영대로). This part of the line was the connection between the line running through Suwon to the station and the country side. The bridge over the main railway line was lifted after 1995, right after closure. But the track bed and everything else is still very visible there. The pictures were taken in July 2013.
This part of the line can easily be seen on Google Earth by zooming in at this location (switch to satellite view as well). The former line is the grey railway line in the map, and this part is the stretch between the (blue) railway line (the Korail main line) and the (yellow) main road to the right of the former line. The length of the track bed here can’t be more than approx. 100 meters.
More pictures after the break.
A map of this particular part of the line. The part between the two red lines (1) is the narrow gauge line in the pictures below. At (2) a new main road has been built. There must have been a bridge here at this point, but it is completely gone. At (3) the line has become part of a park, this is the topic of another article. The part at (4) going to the west is the line to Inchon, which can still be readily found in the country side.