Barcelona is a huge city with a lot of historical things to see. We feel that the best way to explore the city is to enjoy one or more walking tours. It’s a particularly nice thing to do your first true day in Barcelona to help to get oriented. We opted for a walking tour that included the gothic quarter (Barri Gotic), las Ramblas, and Gaudi sites/Sagrada Familia. We had a great experience with Pepito Tours. Our tour guide was incredibly knowledgable and pointed out some hidden treasures in the city–focusing on local restaurants/bars/shops that we could revisit later. We meandered through the confusing streets of Barri Gotic and ended at the Sagrada Familia where we were able to skip the line with our guide. The TI office in Playa Catalunya also offers tours.