Eusebi Guell entrusted Gaudi to create an estate for wealthy people, in Barcelona on land that he purchased in the Monumental zone, high above the city where the air was clean and healthy. Unfortunately the project was not viable and Guell halted it in in 1914. When Guell died his family offered the property to the city council. They purchased it in 1922 and opened it as a public park four years later.
Since then Gaudi has become an international treasure, and his creation was declared a Cultural Heritage of Humanity in 1984. Here are some the fabulous mosaics in the park.

And here is Eusebi Guell himself, standing in the Hippostyle room.