Suggestions for 5 day trip (Dakar)

Hello,
I am fairly new to Dakar, which is where I am settled for a few months. I am interested in taking a trip for around 5 days before my French class starts. I do not speak much French or Wolof yet so I am hoping to find a place in which either it's easy to get to on my own without much negotiation/navigation needed, or I could book with a touring company (suggestions on a company would be great).
I'm looking for a place with lots of nature and water would be a plus. I'm not interested in a big city (looking for a break from Dakar).
Thanks!