From the gates at the Estacion del Norte to the ticketchecks before getting on the platform at the Joaquin Sorolla Station trains are pretty hard to blackride from there. Cheapest solution: get yourself a 1 zone ticket for 1.80e and take a train from the Estacion del Norte
Accommodation & Wild Camping
If you sleep outside, beware of thieves (they are not only in Barcelona). I've had experiences of some "fellows" sneaking around me at night, trying to reach my stuff, pretending that they are not interested or playing friendly after I noticed them. They were both in the big park that surrounds city center like a circle and on the main beach. One night I couldn't sleep normally just because of them.
Good and rather peaceful option for sleeping and camping is Pinedo beach. Just one issue that it's pretty far from the center (~8km). But there are busses from city center (convenient stop near placa de l'Ajuntament) that goes to Pinedo. Ticket is few eur, but it's easy to blackride at least in the last stops (pl. Ajuntamento and ronda de Pinedo), because then driver opens all the doors and don't really cares about anything, so just get in and relax. But it's possible in any stop, just pass the driver and it's a good chance he/she won't disturb you (I saw people doing that).
In Pinedo there are many options. There is a main beach where you can sleep without a tent (I tried one time with a tent just on the beach, but cops woke me up in the morning and told me that it's illegal in all Spain to camp on the beach. If you want to camp it's a better option to walk few km south along the beach where nature stars. There are sand dunes between the sea and main road (on which cops are patrolling at night (they pass few times per night) and they won't see you, just don't shine with a flash light too much and maybe don't burn a fire or try to hide really well in that case. I don't think that they go on the beach and check every dune, but they do pass on the road with a car (the paved road on which normally only pedestrians and bicycles go).
Also on the main beach (close to the town) there is a small wooden house which is a library I think or a museum. It is closed and it has a big outside terrace with wooden floor and a roof all over it. Perfect for sleeping. At night there are almost no people, I stayed there for about one week and had no problems with thieves or something similar. Police do pass as I mentioned, but they either don't see you there lying in the shadow (it's very close to the road) or they don't care, just try not to show up too much if you notice them. It worked just fine for me. Also there are many bushes to hide your stuff in. There are also cold water outside showers both in the main beach and further and drinkable water taps as well. It's a good place if you want to stay for a longer time.
Shower & swiming
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¡Hola! ¿Tienes/Teneis algo para recyclar? ¡Muchas gracias, buenos dias/buenas noches!"
The Mercado Central de Valencia is a great source for fruits, vegetables and sometimes even prepared meals ! Open from Monday to Saturday, from 7am to 3pm/15h.
You can also ask the small "Frutas y Verduras" shops if they have anything to throw out, they are everywhere and mostly run by friendly immigrants.
Busking is completely tolerated by police. And there are a lot of buskers in the old town, especially close to Cathedral.
Free WiFi networks around the city
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