The origin of the Los Arañales wetland in the municipality of Berlangas de Roa (Burgos) is to be found in the old aggregate quarries: after the level of the land was lowered, this led to the flooding of these gravel pits, the appearance of permanent wetlands and, with this, the habitation of a variety of fauna and flora.

The wetland occupies an area of almost five hectares corresponding to four plots of the former gravel pits of Arpape, a company which has an agreement with the Junta de Castilla y León forbirdwatching on this land, where there is also a hut for birdwatching and contemplation.

The bird community in this wetland tends to be mainly migratory birds and other species such as the bee-eater and the stilt warbler, which use this area of reeds and cattails as a resting place.

This natural spot forms part of the Water Trail, which runs through the area between the Guma canal and the BU-120 road, and is almost 15 km long, with a circular route, starting and finishing at Berlangas de Roa. It can be cycled in its entirety.

Access is easy along the route of this path, but you can also get there directly by car by taking a path from the BU-120 road (take an unmarked turning between km 8 and 9, here are the access coordinates: 41.680601, -3.846600).