Sicily: 'It's a whole other country'; streets, roads and parking

Although this is our 4th time in Sicily, it is the first time we've had a car, so the first time we've really confronted the concept of autostrata, roads, streets, vias (little streets), viccolos (even smaller streets) and strata privata (private roads). To be honest, we are still very confused about what is what. I'll post photos so you can see why we are confused.
This sequence of photos shows the entry to a major highway - through a parking lot.

This is a wide road in Sicily.

Here is the turn we didn't take the first few times because it seems to go into a parking lot. 

But no, if you follow the flow of cars which take the dog leg uphill, through the parking lot you arrive at a highway. Not a very safe entrance, but there you are. 

Major highway.

Entrance to the autostrada.