Dirt Roads/Paved Roads

[Ramm]

I have two questions that I ask in idle curiosity.

Are dirt roads in the game really unpaved? Or are they just paved secondary routes?

Are single hex paved roads only two lanes? Or can they mean more than two lane?

The reason I ask is because when I was playing just now the map I was using had a single "dirt road" that went straight through a LA style city grid! It was incongruous to see a single "dirt road" cut through a urban area composed modern city blocks, all of which were paved.

I realize that the road type is just eye candy but "knowing" will make me enjoy the game more.