GPS Upper Mississippi Chart??
 

Hello all-

I would like to add a small GPS plotter this season like the Garmin 172 or
182 however I have not found a source for navaid charts on the upper
Mississippi. Since I am always in site of shore I was wondering if the
marine basemap supplied with these units will be suffice as a quick
reference of where I am and how far to the next lock, etc. Thanks.-Dan