The Circunvalación is a flat walking route that circles Coroico along the bed of a railway to La Paz that was started in the 1940s but never finished. You can still make out the flattened terrace where the Coroico station was meant to stand. It is by some distance the easiest walk in the area and the best gentle introduction to local life in the Yungas.
The path threads through coffee and banana plantations, terraced coca fields, mango trees and citrus orchards, with stretches that follow rarely used trails where you may spot snakes, birds, squirrels and great drifting clouds of butterflies. Because the route follows an old railway grade, it stays more or less level throughout, which makes it ideal for an undemanding half-day out or an easy first walk before tackling the steeper hikes around town.
On clear days the views over the Rio Coroico valley are superb, with the forested mountains stacked up behind. You can walk it independently in either direction; bring sun protection, as parts of the loop are exposed, and allow extra time to stop and watch the wildlife.