We will be arriving in Barcelona in the late afternoon after many hours of travel. i'm thinking the first full day will be exploring La Rambla area, El Born and El Raval ending at Barceloneta. Hit a few sites in those areas. Day two would be Sagrada Familia and the rest of the Gaudi world in Eixample. La Pedrera, Parc Guell and Casa Batllo. Day three will be a day trip to Monserrat and the morning of day four Montjuic.
We can't extend for more days because we leave on the evening of day four for Cadiz (two days) then Sevilla for three days. On to Cordoba foe a one day visit then Madrid for three days. Probably work in a day tour to Segovia or Toledo. I know it's a bit rushed but we have to work in as much as we can this trip. We have been to Madrid before as well as Malaga, Granada, Ronda and Estepona.
I would appreciate any comments, many thanks