Traveling the wide and very brown Sambú River is a memorable experience: you'll glide past spectacular mangroves – five of the world's seven known species grow here – deep jungle and, beyond Sambú and Puerto Indio, traditional villages. A trip up the Sambú is a real adventure, something that may not be possible anywhere in the tropics 50 years from now. Even if you traveled deep into the Amazon, you'd be hard-pressed to find such wilderness.
Be warned, though, that it's not everyone's cup of tea. You'll probably need to bring several large containers of gas from La Palma (where you'll arrange boats and guides for this section of the trip) to fuel the canoe you hire upriver. Other hardships include a lack of showers and toilets and an abundance of creepy crawlies.
At night you can make camp if you have a tent or a jungle hammock. However, your boatman may prefer to make a deal to sleep on the floor of an Emberá or Wounaan family's home. If you can speak Spanish, finding a family to move in with for the night won't be difficult, and you might even get a hot meal.