Getting there & away
Numerous buses between Jujuy/Salta and the Bolivian border at Salvador Mazza stop at Libertador General San Martín and Calilegua, and some will let you off on the highway at the junction for the park.
The access road heads west from the highway 3km north of Libertador, and 2km south of Calilegua. It’s 8km to the ranger station at Aguas Negras; there’s enough traffic to hitchhike.
A daily bus (at 8:30am) goes from Libertador General San Martín to Valle Grande (two hours) through the park. It passes the Aguas Negras ranger station at 9am. The return bus passes around 6pm; perfect for day trips to the park. It’s also easy to get a taxi from either Libertador or Calilegua to Aguas Negras (AR$10 to AR$15).