Lago Tarapoto, 10km west of Puerto Nariño, is a beautiful jungle lake fed by the Río Amazonas, and is home to pink dolphins, a tiny population of manatees and massive water lilies. A half-day trip to the lake in a peque-peque (a low-slung wooden boat) from Puerto Nariño (around COP$50,000 for up to four people for around four hours) is the main draw for visitors, who usually take a dip in the gorgeously clear water. Piranha fishing is also possible here.