The Rio Agrio Waterfall is located in the small town of Bajos del Toro. This town, about two hours from Costa Rica’s capital of San Jose, is best known for its many waterfalls. The Rio Agrio is one of the area’s most visited because of its relatively easy access. Rio Agrio translates to “Sour River” because of its very low pH. The nearby Poas Volcano emits acidic ash and gases, which collect in the watershed and run downstream. The Rio Agrio Waterfall is on a larger property that also has a dinosaur park, viewpoint, restaurant, and down the street, some blue swimming holes. After checking in at the reception, you’ll make a short walk up the hill toward the trail entrance (5-10 minutes). It is off to the right of the Dino Land entrance. You also can connect with this trail from the end of the Dino Land exhibit. From the trail entrance, the hike/walk to the Rio Agrio Waterfall is a short 0.4 kilometers (0.25 miles) each way. The trail to the waterfall is well maintained and mostly concrete but can be wet and slippery. There are some steeper inclines and steps. You’ll also cross a couple of small, sturdy metal bridges that bring you over the river.