Now a peaceful library surrounded by gardens, this corner of Retiro Park was once the second-oldest zoo in Europe, known as the Casa de Fieras, or “House of Beasts.” 

In 1774, King Carlos III of Spain ordered the construction of the House of Beasts, a primitive concept of what we know as a zoo. It was the second animal park built in Europe, after the zoo in Vienna. It was home to lions, tigers, and bears, as well as monkeys, ostriches, a crocodile, and even an elephant.

There are many stories surrounding the park, such as when the elephant, named Pizarro, escaped, fleeing down the central street of Alcalá. According to one darker myth, during the Spanish Civil War, some 20 to 30 prisoners were thrown into the cages to be devoured by the animals.

Back in the 18th century, it was common to see fights between animals of different species, like lions and bulls. In fact these spectacles were highly popular among the aristocracy and were used in all sorts of celebrations. 

By its final days, the facilities were not large enough to accommodate the growing number of animals and visitors, which reached as many as 200,000 people on some weekends. The House of Beasts was permanently closed in 1972 when the current zoo and aquarium were inaugurated at a larger space at Casa de Campo Park.

In 2013, the historic zoo was converted to a library and botanical garden. Today, books are stacked on shelves in structures that once caged wild animals. However many of the original structures from the zoo have been preserved. You can still see the old bear cages, the monkey pit, the lion’s den, and remains of the bars through which the great beasts were fed.  Moreover, the house of beasts is not quite entirely without its beasts, albeit those that remain are somewhat tamer and at liberty: Some beautiful peacocks can be found wandering around the park and if you glance up at the treetops,  you might see some invasive quaker parakeets, a species originally from Argentina.