Enjoy morning pickup at select Salta hotels; otherwise meet your guide and group at a centrally located point. Board an air-conditioned, 4x4 tour vehicle for the ride to El Rey National Park, located 125 miles (200km) outside the city limits. Meet a park ranger at the entrance to El Rey National Park, and listen to a brief orientation to the area. Continue to the Popayan trailhead and set off into the rugged terrain, across streams and rivers that can only be forded by a 4x4 vehicle.  Pause where the La Sala River and the Popayan River converge, where the clear waters allow to get a look at the marine inhabitants. Spot shads, gold fish, catfish and breams swimming in the pristine water, then explore the transition and Chaco forests before returning to the Popayan trailhead. Take a break for lunch (please bring your own food), then head north to the Casacada of Lobito waterfall, a favorite hangout for the local otters. Journey through the mountainous jungle to Pozo Verde, where you can see the different vegetation that grows at higher elevations. Your guide will point out the tree species that can only thrive at higher elevations (here 4,953 feet/1,400 meters) such as Laurels and Cedars. Keep your camera poised for shots of bird species such as coots, kingfishers and herons or wildlife such as otters, peccary, tapir and the elusive puma. Begin your journey back to Salta and end your tour with hotel drop-off.