Who has travel tips for me?

So as I said I’ll be spending the summer in Palamos, Spain. I have to work 6 days out of 7, but on my free days I’m hoping to explore my surroundings a bit.

I know Girona and Barcelona are relatively close, but other than that, is there anything I should see? And what should I visit in Girona and Barcelona?

I’m definitely planning to leave a little early so I can spend a few days in Barcelona before I go to the camping. I’ll look for a place to sleep on couchsurfing, but where should I eat? What are nice places to go out? What should I see?

Later in the summer my whole family is planning a citytrip in Barcelona. I’d appreciate a few tips that are good for a large group and small kids as well. We’re a group of 16 people, the kids´ages vary between 15 and 5 years old.

And on another level, what are the cheapest mobile internet options? I’m hoping there is wifi on the campingsite I’ll be able to use, but if not I want a cheap dataplan. Here in Belgium I pay 15€ a month for 1GB, which is probably as good as it gets but it doesn’t work internationally. Anybody has a good tip for me here?