CUV-9142, 8, 16340 Cañada del Hoyo, Cuenca.
From Teruel N-330 33 km to Torre Baja, N-420 41 km, in Cañete turn right CM-2106 8 km to Campillos-Sierra, turn left CUV-9142 26 km towards Cañada del Hoyo.
Siete Leguas: no set open hours.
Siete Leguas: Adults EUR 2, Children EUR 1.
|Guided tours:||self guided|
Marqués de Cantarranas (2001):
Paisaje Lacustre de Cañada del Hoyo
Adolfo Eraso Romero, Victoria López-Acevedo Cornejo, Miguel Ángel López Muliloz (1979): Estudio de las torcas de Palancares y Cañada del Hoyo en el karst de la serranía de Cuenca Revista de la Sociedad Geológica de España, Grupo Espeleológico Vizcaíno (9). pdf
|Address:||Lagunas de Cañada del Hoyo, CUV-9142, 8, 16340 Cañada del Hoyo, Cuenca.|
|As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then.
Please check rates and details directly with the companies in question if you need more recent info.
|2007||declared a Natural Monument by the Junta de Comunidades de Castilla-La Mancha.|
Lagunas de Cañada del Hoyo (Lagoons of Cañada del Hoyo) is a group of dolines on a limestone hill northeast of the village Cañada del Hoyo. The name "lagoons" refers to the fact, that seven of them are water-filled. The lagoons were used for swimming and have names. The three upper lagoons Gitana lagoon o de la Cruz, Laguna Tejo and Lagunillo Tejo are located on public ground and may be visited for free. The other four are located at the foot of the hill and called the lower lagoons. This area is owned by a farmer, the farm is named the Siete Leguas (Seven Leagues) farm. The lagoons are named Laguna Parra, Laguna Cardenillas, Lagunillo Tortugas and Laguna Llana.
The most spectacular feature of the lagoons is their colour. Karst springs typically have a blue or turquoise colour which is caused by the high content of dissolved limestone, which filters sunlight except for the blue wavelengths. Depending on the actual minerals it may also appear green. But these lagoons contain mostly rain water and have neither inflow nor outflow on the surface, so the standing water has a growth of microorganisms, especially algae, which cause other colours. One of the lagoons has an intensive pinkish purple. But the colour is caused by the filtering of the light and so the colour is quite intensive when the sun shines on the water. In the evening they become quite dark blue, almost black. An if you fill some water in a glass its perfectly clear, the colour is an optical filtering effect, not caused by pigments. Also, the colours caused by microorganisms depend on the amount and kind of microorganism, in other words the season of the year and the temperature.
To understand the water in the dolines we need a little geology. The limestone is karstified and there are underwater caves, filled with groundwater. These caves collapse if the chambers become too big and the ceiling too thin, which creates a circular collapse doline. The collapsed material fills the collapsed chamber and there is actually no cave entrance, but the boulders at the floor have gaps between them, which are filled by groundwater. And while there is actually no current, the water which evaporated is replaced by water from the groundwater. All the lagoons actually have the same height, as they are just different parts of the groundwater. There are actually 34 dolines on this hill, but if their bottom is higher than the groundwater level, they have no lagoon inside.
In this area the local term for doline is torca. There are numerous such doline fields in the area with dozens of dolines. And the dolines have an impressive size, they have diameters of up to 200 m. Dolines are actually classified by size, and dolines which have a diameter and a depth of more than 100 m are called tiankeng. The dolines here have the right diameter, but normally they are only up to 50 m deep, which means they are too shallow to be called tiankeng. Nevertheless, they are quite impressive. And most of them are circular, almost perfect circles.
The Laguna de la Gitana (Gipsy Lagoon), which is also called Laguna de la Cruz (Lagoon of the Cross), is a meromictic lake. This means it has layers of water that do not intermix. There is a border, about 13 m deep and different layers of water above and below. And it has another specialty, typically once a year in summer for one week the fenómeno blanco (white phenomenon) occurs, generally in the second half of July. The clear blue-green becomes a milky-white blue, caused by the precipitation of magnesium carbonate and calcium carbonate in the form of dolomite and calcite crystals. It is caused by the photosynthetic consumption of carbon dioxide from the water by phytoplankton that grows in the lagoon. With the loss of carbon dioxide the water is not able to keep the limestone dissolved, and it precipitates.
Spain is a warm and rather dry country, many areas in the south are semi-arid, with almost no rainfall during summer and high temperatures. Water is of great importance, for drinking and for irrigation, but also for a refreshing bath in the summer heat. As a result the lagoon are under threat, the pumping of groundwater from the aquifer lowers the water level and thus the lakes. Also, the number of visitor to the lake which were swimming here grew substantially over decades. In the 1980s the number of visitor reached a level, which cause the originally blue Laguna de la Gitana to become green. The massive effects on the lagoons, including littering and the change of the biochemistry and thus the colour, became too much. The site is now a nature preserve and bathing is not allowed anymore, but there is so far no cure for the lowering of the aquifers.
A last word on visiting the site. It is located at the road and there are trails to dolines. The deeper dolines have outlooks, and there are trails down to the lakes. The four lakes on private property have open hours and a (nominal) fee. It seems the farmer intended to earn a few bucks with the lakes, and we can only guess the nature protection banning bathing made this venture quite unsatisfactory. Websites and reviews say it is quite neglected.