This is a roughly 4742.82-mile long trip through the the highest number of connected and landlocked countries you can travel through. I set out to find out the shortest trip between the highest number of landlocked countries you could drive through on Earth, as I noticed that many land locked countries are near each other. I wanted to avoid driving through more than one country once or going into non-landlocked countries, but this wasn't really feasible. I quickly sidelined this issue, unless it was a particularly egregious instance of doubling back. I didn't have to enter any non-landlocked countries though, which is nice. I did a similar trip through Europe's connected and landlocked countries.
There are two areas where Google Maps does not have roads labeled, so I had to mark the route myself. The roads across the Niger-Chad border are not often used and they can be dangerous to travel on. For these reasons or perhaps others, they don't appear on Google Maps, so the complete route can only be see via the Google Earth files. The other area without roads is Akobo, South Sudan. Here, I marked the path to get to the Pibor river, where you can cross into Tirgol, Ethiopia. You can then follow the same path back into South Sudan to continue the journey.
I would take caution if you actually attempt this trip, as some of these areas are dangerous to travel through. Particularly, as of 7/29/2023, Burkina Faso, Mali, the Central African Republic, and South Sudan all had Level 4 Travel Advisories placed on them by the U.S. State Department.
Included below are resources to view the trip in Google Maps and Google Earth.
Here are the legs of the trip on Google Maps, without the unmarked portions between Legs 1 & 2 and Legs 2 & 3:
Here are the legs of the trip on Google Earth: https://drive.google.com/drive/folders/1upQiVC_a_A4cnHFkhPXDhmqCiJn5UoOA?usp=sharing
Special thanks to https://www.gpsvisualizer.com, as their tools are what makes creating the Google Earth files possible.