Traveling to morocco?

So I'm a female always loved the moroccan culture and decided to take a flight to marrakech. Instead I'm landing in casablanca for a 13 hour layover and rented a car. I know some people there and they told me casablanca Is beautiful to view but a 13 hour layover seems a bit much that I should just skip it get in the car and drive straight to marrakech. They don't drive so I have no way in going back to casablanca hopping on a plane just to come back to the house I rented it's all a mess and I need some advice thank you.