Okay I'm going to chime in here.
I have purchased and used Geo-textile matting manufactured by Amoco. I purchased it through Price & Company (Grd. Rapids). Not cheap. Overa buck per foot, so use it wisely.
It works very well in for road construction through wet areas. To build a whole road would obviously be very expensive! I have only used it sparingly to get cross small (150 feet) wet areas that are common in the Great Lakes States.
There are many different grades of matting. I have used the industrial strength stuff that is nearly 1/4" thick. Jeff's photo shows the thin stuff that is used more for holding banks, soil erosion, and landscaping applications. I'll try to get a digital photo of the stuff I use.
Good topic and discusion. Wakefield you know that you can track all your property improvement expenses and claim them on your taxes. Check Bill Hoover's site at Purdue University. Good luck y'all.