aceptamos:

Haven’t you decided to book a car by a car hire yet? A rental car is the best way to visit Barcelona and the surroundings. We specially recommend visiting the province of Barcelona driving north, to the Costa Brava. If you decide to rent a car with our car hire service you will find many interesting places in Barcelona that normally you wouldn’t visit.
We suggest to plan a sightseeing and visit Barcelona with a hired car. It´s the best way to get to know the many sights to admire. Duty visits are the famous Park Güell, the Gaudi's unfinished masterpiece the Church Sagrada Familia, the houses Casa Milà and Casa Batllo also by Gaudi, the Cathedral of Barcelona, La Rambla promenade, the Aquarium and many more attractions that Barcelona has to offers you.
Here you can read more about Sightseeing in Barcelona:
http://www.spanish-fiestas.com/barcelona/sightseeing.htm