This is the border with Gambia south in Casamance after Velingara town. Here things run pretty smooth and people are quite relaxed about tourist due to the few number of them actually passing countries here.
If you come with car you will need carnet de passage en douane, unless you can make the head police understand the document is only for cars older then 4 years (which is not, but he doesn’t know the law), so you just saw you pay the duane for the car and you want to enter. Its nice to have some pencils and t-shirts which they will love if you say you will give them that after you have the douane for your car made of course.
Coming by foot, you have transportation in Velingara going to Georgetown, or you can just hitching which I think will be ok since I haven’t seen much dangerous things in the country…

border senegal gambia africa border crossing