At Plaça de la Boqueria, where four side streets meet just north of Liceu metro station, you can walk all over a colourful 1976 pavement mosaic, with one tile signed by the artist, Miró. The mosaic's bold colours and vivid swirling forms are instantly recognisable to Miró fans, though plenty of visitors stroll right over it without realising. Miró chose this site as it's near the house where he was born on the Passatge del Crèdit.
The mosaic was the epicentre of a terrorist attack in August 2017 and the 14 victims are commemorated here with a 12m-long engraved memorial inscribed with an anti-violence message in multiple languages.