How the racing track in the demo car project in the unity3d asset store was made?

I have downloaded the demo car project available in the unity asset store to learn racing game with unity 3d. Now, i am curious to know how the racing track in that project was made. Was it made using road making tools like Easyroads3d, path road tool or it was made from the scratch using 3d development software like 3ds Max, Maya, Blender etc? It would be good help if you let me know which package or software was used? Please let me know at your earliest convenience.