The Calares del Mundo y de la Sima Natural Park is a protected natural area located in the southwest of the Spanish province of Albacete, in the autonomous community of Castilla-La Mancha.

It covers a mountainous terrain, marked by several watercourses, including the Mundo river, which have eroded the calares and created karst landscapes of great beauty. It extends over a total of 19 192 ha, in the former natural region of the Sierra de Alcaraz, between the municipalities of Cotillas, Molinicos, Riópar, Vianos, Villaverde de Guadalimar and Yeste, within the service associations of the Sierra de Alcaraz and Campo de Montiel and the Sierra del Segura.

The natural park is made up of the areas known as Calar del Mundo, Calar de en Medio, Chorros del río Mundo, Poljé de la Cañada de los Mojones, Sierra del Cujón and Calar de la Sima. Apart from its aforementioned geological value, its great variety of flora and fauna is of utmost importance. More than 35 endemic plant species speak of a time when the flora fled the glaciations and settled on the Iberian Peninsula, later remaining confined to very specific enclaves, such as high mountains similar to those that make up this natural park, thus justifying the number of unique plants found there. The animal wealth includes endangered species such as, for example, the golden eagle, Bonelli's eagle, griffon vulture, eagle owl, mountain goat, etc.