I alway stay at the Barcelo Raval, done so numerous times, nice place in a good location. A friend calls it The Glitter PalaceI went recently for a long weekend.
Stayed at the Barcelo Raval, which was about 5 minutes walk to La Rambla, but on the "edgy" side of the town centre (equivalent of Shoreditch / Whitechapel in London), so a bit scruffy to walk from but I never felt unsafe. It's a big chain hotel with a polished boutique-y feel, similar to Malmaison, and has a great rooftop bar with decent views of the city (10/11 storeys high). There were loads of tiny, but great quality, restaurants in the streets around.
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I love Barcelona and usually go at least once a year. Amazing city.