Swim at the Paradise Pool in the Río Pacora

This place is called Paradise for a reason. Starting off from the Kalu Yala base camp (you can learn more about staying at their site here), it is just a ten minute hike to the swimming hole. Through the main gates, you go right (downhill) to the river crossing. Cross the Pacora, and then start walking up the road on the other side of the river. You will enter the first gate on the left. Be sure to close the gate after you - there are often cows and horses in the field. Follow the path straight through the pasture until you reach a second gate. Go through this (again, be sure to close it), and follow the trial past the little picnic site until it starts veering to the left. This part of the trail will take you down to the river, just upstream from the swimming hole. Hug the shore of the river until you make it to the site. After the little cascades, there's a nice spot to put your belongings. 

Then, you can either clamber up the side of the earthen wall to get to the jumping deck, start one of the free solo routes on the large rocks of the right (up to V2), or take a spot on one of the rocks on the left (great for back flips and people watching).

While you can spend loads of time doing just that, if you venture a bit further down stream, there is a troop of howler monkeys that often spend their time in the trees just next to the river on the right. There are trees to climb and a million different things to catch your eye over in this wilderness. 

It's definitely a favorite spot, super easy to get to, and something you cannot miss if you are in the Los Tres Brazos Valley.