Ontígola Sea., Aranjuez

The Natural Reserve of El Regajal-Mar de Ontigola is a natural space of the Community of Madrid, which has been protected since 1994, according to Decree 68 of June 30. It is located in the southern part of the region, within the municipality of Aranjuez, and has an area of ​​629.21 hectares, along which two main environmental units converge: the wetland of the Ontigola Sea, a reborn reservoir today completely naturalized, and adjacent lands, among the which highlights the farm of El Regajal, a Mediterranean-subdessert mountain that houses great entomological diversity.

The first unit cited brings together important communities of palustre vegetation, which give refuge, temporarily or permanently, to numerous aquatic birds. The second, on the other hand, constitutes one of the most important butterfly reserves of the planet, with species such as Plebeyus Pylaon, Iolana Iolas and Zerynthia Rumina. In 1979 entomologists belonging to the International Union for the Conservation of Nature cataloged El Regajal as the fifth world priority in the conservation of lepidoptera.

In addition to its natural wealth, the reserve shows important historical, cultural and architectural values, the result of its close relationship with the Royal Site of Aranjuez, to which the Ontigola Sea was supplying water from the 16th century to the mid -twentieth century. His prey, in which architects such as Juan Bautista de Toledo and Juan de Herrera participated, marked a milestone in the history of modern hydraulic engineering.