I made this design back in 2013 on Autodesk 123D to upload on shapeways (1010696). I originally designed everything hollow to save on cost. My account there has since gone inactive and all my products were deleted from their site. I found the files on my old laptop and figured someone may want to use them. 

The roads are 1-to-1 with standard Catan pieces. The settlements and cities are similarly sized but themed a little differently.