This place owes its name to the railway's branch (Ramal) that starts in Perico and runs northbound towards Santa Cruz de la Sierra, in Bolivia. It is a space in which the leafy vegetation and rich fauna invite to mystery and endless astonishment.

Eco tourism and adventure tourism are the best choices for this beautiful scenery. This is a representative area of Las Yungas or Sub Tropical Mountain Forests. Its biological diversity is amazing and allows one to enjoy the different alternatives of contacting nature without altering the ecosystem.

It comprises the Parque Nacional Calilegua Park, Valle Grande, San Pedro, Palpalá, Aguas Calientes (thermal waters), Palma Sola and the Zapla mountain ridges, where the Altos Hornos (High Furnaces) are sited.

This is an ideal region for photo safari, flora and fauna observation, trekking, horse riding and four wheel driving.

One on the nicest seasons to enjoy this circuit is during southern hemisphere's spring (September-December). During this season, life flourishes and shows off all its shades of greens, along with the coloured lapachos and the singing of the birds.

This is the least high zone, and it is damp and warm. The waters of the Rio San Francisco river (formed by the Grande and Lavayén rivers, and a tributary itself of the Bermejo river) are intensely used for irrigation.

Existing from the very beginning of the colony, the sugarcane cultivation is predominant. Other present cultivations are citric, avocados, bananas, papayas, mangos, cherimoyas and first class vegetables, visible mainly from the road to Palma Sola and Santa Clara.