Here’s a great map that shows all paved and unpaved (dirt, gravel, etc.) roads in an area. It’s a really useful tool if you need to design a long gravel ride or bikepacking route.
Report from a quest to find and update out-of-date road surface tags in Victoria, Australia.
Maps, table and charts on the distribution and length of sealed and unsealed major roads (from motorways to tertiary roads) in all states of Australia.