Lagunas de El Tobar

The hamlet’s lakes

El Tobar is a hamlet of Beteta; it lost its town council in 1973. Leaving the village, a dirt track leads to its lakes: the Pequeña, the Ciega and the Grande, basins opened as water dissolved the limestone. Around them, woodland thickens on the shaded slopes, and mosses and lichens cover rocks and trunks.

La Grande is the largest and deepest, with an unusual feature: two layers of water that do not mix. Above is fresh water from the Arroyo del Masegar and springs; below is saline water seeping through salt-bearing rocks, up to three times saltier than the sea. In early summer white water lilies cover its margins, and waterbirds shelter in the reedbed.

What has changed the lake

La Grande straddles the municipalities of Beteta and Masegosa; in Masegosa it is called Laguna Grande. It formed around 200,000 years ago through limestone dissolution. It covers around 17 hectares and is 18.6 metres deep at its deepest point, beside the north-western cliff, holding 1.4 million cubic metres, roughly the volume of the Camp Nou. It is meromictic: below around twelve metres the saline water never mixes with the water above, a rare feature shared by only a few lakes in the peninsula, such as Banyoles.

Its landscape has changed greatly. In 1629 Juan Pablo Mártir Rizo spoke of three large lakes; today there are two main ones, La Grande and La Pequeña. In the 1940s crops reached the shore; twenty years later basket willow dominated. Around 1967 a canal was opened beneath the hill to bring water from La Tosca reservoir, maintain a constant level and supply the Puente de Vadillos power station; since then the lake’s catchment has included the Cuervo’s, and its water sometimes becomes cloudy with water arriving from the reservoir.

Plan your visit

Before you travel

The SL-CU 4, an SL (local trail), starts at El Tobar’s communal washhouse and traces a figure of eight between the three lakes: 5.5 km, easy. Do not tread on the shore or enter the reedbed.

Combine with

The Hoz de Beteta, to the west, and the PR-CU 90, a PR (short-distance trail) also starting in El Tobar. altotajo.es describes Laguna Grande’s geology in its own entry.