Barceloneta Beach is younger than many of the people swimming off it. Until the city rebuilt its waterfront for the 1992 Olympics this shore carried rail track, workshops and beach restaurants built out over the water; breakwaters went in, and a bathing beach replaced a working one. Today it is one flat strip of pale sand, busiest in the middle of the day and loudest in high summer: volleyball, hand drums, vendors calling mojitos along the waterline, grilled-fish smoke off the terraces.
The neighbourhood behind it is far older. A grid of tight blocks was laid out in the 1750s on silt that had banked up behind the harbour wall, to rehouse people whose district was demolished for the citadel. The buildings were kept shallow so that every room could reach light and sea air. A sail-shaped hotel closes the view to the south-west and the masts of the Olympic marina mark the far end. None of the sand is permanent: winter storms cut metres off the width in a night, and out of season the strip empties into a walkers' beach of wet sand and grey swell.