Parque del Retiro

125 hectares in the middle of the city and a UNESCO World Heritage site since 2021.

What to actually do: the Palacio de Cristal (free, usually a contemporary art installation inside), the rowing boats on the lake, the Rosaleda in May, and the Bosque del Recuerdo. Sunday afternoon around the lake there are drummers, jugglers and a tarot reader who has been there for decades.

Free. Gates close after dark; hours change with the season.