Creating Road Maps in Adobe Illustrator

1. began w/ drawing a straight line (using hold Shift) on my new document.

2.Copied and pastde the line back into place (Ctrl / CMD + F), and change the weight to a thinner stroke and colour in white.

3.
Selected both of the objects strokes and clicked the 'New Brush' icon in the brushes window.

http://www.webdesign.org/web/vector-graphics/adobe-illustrator/creating-road-maps-in-adobe-illustrator.16104.html