We realy enjoyed our stay (2 adults, 2 kids) in barcelona. The flat is located in the center of Poble Sec, which is west of the very city center of barcelona. You can walk to famous rambla in 15 minutes. There is a metro station in 5 minutes walking distance. Taking this metro line will bring you within 15 minutes to La Sagrada Familia or in 5 Minutes to Rambla.
Close to the apartment are many small Tapas Restaurants.