<human>:  When was the Casa Milà built?
<bot>: The Casa Milà was built between 1906 and 1912. It was designed by the famous architect Antoni Gaudí. The building was constructed as a home for the wealthy industrialist and art collector Eusebi Güell. The building was designed in the style of a medieval castle, with many arches and windows. The building was also known as the Palau Güell, which means "Güell Palace."