I installed the California, Oregon Washington and Alaska Topo Maps on my PC. Using Mapsource, I loaded selected Topo sections (and City Navigator) to my Garmin 76CSx. The gmapsupp.img file is just over 1GB.
On Mapsource, I can see various details that are not included in City Navigator - including unpaved roads, contour lines and streams. But when I view on my GPS (scrolled and zoomed-in to the 500ft level), I can only see City Navigator details. All of the selected map sections appear in the 76CSx map list.
Any ideas?
Yes, disable City Navigator on your gps to see the Topos
Thanks for your quick and helpful response.