Isla Bastimentos. It's in an archipelago that was like a pirate enclave back in the day where they speak a mixture of Spanish, English and French. Very cool place, I go to that region at least once a year actually - But that first one I was pretty naive and did what you shouldn't do, which is consume tap water (even if boiled) on a tropical island.
What's fun to do in that region is waking up early to take one of the speedboats that drops you off on cayes zapatillas, which are these small islands you can walk around in around 20 minutes. Make sure to bring water and wear sunscreen of course, but you get to feel like you're on a treasure island for a day and there's good snorkeling/diving reefs around there as well.
Just once. Drink bottled water when you go to these places. They are tropical islands covered in jungle trees where pumas swim between these islands, it's not that hard to realize why when you think about how water flows in a place where everything is trying to kill. It's terrifying until you realize all nature isn't disney.
What's fun to do in that region is waking up early to take one of the speedboats that drops you off on cayes zapatillas, which are these small islands you can walk around in around 20 minutes. Make sure to bring water and wear sunscreen of course, but you get to feel like you're on a treasure island for a day and there's good snorkeling/diving reefs around there as well.