My god, hipdoc, San Sebastian, just don't doubt it !!! San Sebastian is considered here in Spain as one of our most beautiful cities and it has a very good beach (the water is cold, though..it's the north). Royals went there for the summer till the thirties (when the Spanish Civil War began) and it's full of beautiful buildings, good shopping and the best of spanish food.

Marbella has seen better days...sure. I mean , it's not ugly but it's just a vacation resort..good for its location to do day trips but nothing special to see there, I just don't like it at all.

I have not been in Barcelona... however, I have been in Malaga and Marbella, my husband and I are in our 30's and if we go again, for sure will go to Barcelona. I f you are thinking about going to Marbella/MAlaga to visit Nerja, Ronda, Mijas and all the little towns let me tell you that are cute but fill with turists, beaches are not good and I'm sure Barcelona will be great.

Ok, let me tell you that we enyojed Sevilla a lot, Jerez de la Frontera (visiting the wineries) also the little whitw towns, we had a funny story in Jaen, we had a great experience there with the people because this is not a turist town, so everybody was asking us what we were doing there, and giving sugestions about places (there is not much to do, but we stop there just to spend the night) so for us that was a very "Spaniard place"

Nerja, Mijas and Ronda (nice towns)were full of turists, everything is in english, French, German,didn't fell authentic and most of the turists are Seniors.

We also are in the city (NYC) but the flavor of Madrid is great and the people is also great (a little bit rude but like NYC). LOve spain!

I can only say that i loved seville and barcelona. the architechture, people, vibe. I would return to either city in a heartbeat - Madrid - ok for a couple of days...costa del sol - keep it!

Rule out Malaga for sure. Not that interesting in my opinion.

Barcelona would probably be the best choice. There's beach and lots of sites and good food. Plan to do lots of walking here.

Marbella would be nice if you are looking for a resort beach type vacation. It's very beautiful there.

Have fun.

Do Barcelona:
Then daytrip to Montserrat, Cordoniu Cava, and Andorra by car if you see it all.