Map Nr. 4 is up for sale on RPGNow (http://www.rpgnow.com/product_info.php?products_id=92698&affiliate_id=313911), DriveThruRPG (http://rpg.drivethrustuff.com/product_info.php?products_id=92698&affiliate_id=313911) & WargameVault (http://www.wargamevault.com/product_info.php?products_id=92698&affiliate_id=313911) (and soon at Paizo and IPR as well).
With our latest map we continue the River & Mountains theme, but in a perhaps rather unexpected way, for it shows a hidden lake high up in the mountains (fed from said river, though). Other terrains features: a grotto veiled behind a waterfall, lots of looming cliffs and gaping cave entries... all in all it's an eerie place ready for the PCs' doom.
Again, we include a quite unique 3D model of the terrain; we provide verbal descriptions of the place, additional landscape views... and of course the large format relief map (and grid, elevations, contour lines).
For previews and information, check out our website (http://3rd-supplement.com/).
Game on!
Heiko