I got an idea from here: https://forums.civfanatics.com/threads/roads-rails.399942/
Road: Green
Railroad: Blue
Pillaged road & railroad: Red
There are two zip files; mod ver, and dlc ver. Choose one which you want.
Colorful Road (v 1).zip : mod version. \Documents\My Games\Sid Meier's Civilization 5\MODS
ModDLC.zip : dlc version. \Steam\steamapps\common\Sid Meier's Civilization V\Assets\DLC
Road: Green
Railroad: Blue
Pillaged road & railroad: Red
There are two zip files; mod ver, and dlc ver. Choose one which you want.
Colorful Road (v 1).zip : mod version. \Documents\My Games\Sid Meier's Civilization 5\MODS
ModDLC.zip : dlc version. \Steam\steamapps\common\Sid Meier's Civilization V\Assets\DLC