Texas as roughly 5x the size of NC by landmass, and has approximately 3x the number of road miles. However, NC is more densely populated than TX. If you look at it by road mile per person they are almost identical.

And North Carolina places a particular emphasis on paving every road. It's pretty much impossible to find a public road in NC that has street signs and stop signs but is unpaved. The only ones I can think of offhand are in state parks. By contrast, on a recent trip through western Maryland there were about two major roads that were paved for their entire length and the rest reverted to gravel in the more remote areas.