Las Arenas is a part of the city's main sandy beach and a good place where to take a swim. This place is well-equipped for various sports and also well-facilitated with showers, toilets and medical care stations.
When hungry, hop into one of many restaurants lining the beach, serving fresh seafood.
Wikipedia https://sv.wikipedia.org/wiki/Las_Arenas_beach
More information at visitvalencia.com http://www.visitvalencia.com/en/what-to-visit-valencia/valencia-beaches/el-cabanyal-las-arenas-beach
Address 46011, Spain
Coordinates 39°28'5.706" N -0°19'20.084" E