If you had a few hours in Barcelona, start your journey from Plaça de Catalunya walk down the La Rambla and turn left to thr Gothic quarter. Roam narrow streets till you reach to the Cathedral and see Pont del Bisbe. Walk down to the sea bank and turn right to walk along the seafront till Columbus monument. Walk up to the La Rambla again and turn left to the streets of El Raval until the Universitat. Should you have a bit more time visit Plaça d’Espanya. You won’t regret.