Rural around here in the PNW, the vast majority of rural roads are paved, except for forest service roads and the odd road here or there. I do a lot of countryside cycling and it's rare that I encounter a gravel road.

What they don't always have is the smooth surface found on highways; it's paved but of a bit of a rougher type (don't know all the technical differences, but it's noticeable on a road bike).