Start at Pelayo Street, one of the main commercial streets in the city, which runs past the Plaza de la Universidad and divides the oldest and newest parts of the city. Continue through one of the biggest squares in Spain and one of the most important places in Barcelona, Plaza de Catalunya. From here, walk down one of the most beautiful and famous avenues of the city, the Ramblas. Walk the length of the street, passing by many flower and souvenir stands along the way. As you stroll, the guide will tell you how Emperor Augustus founded the city, and how he chose the name. You'll then arrive at the old port of the city. See the remains of the old city wall as you walk through the narrow streets of the Gothic Quarter, before arriving at Nova Square. Here, in the center of the Gothic Quarter, you'll be able to admire the Cathedral, built in the Gothic style.  From your guide, hear about important figures in the history of the city, such as St. Roque, or Wilfredo the Hairy. You'll also learn more about the flag of Catalonia and how its current design came about. Next, walk around Plaza del Rei and Plaza del Pi, until you reach Plaza de Sant Jaume, the current administrative and political center of the city. Finally, see the town hall, and the Palau de la Generalitat.  At the end of the tour, you have the option to go to a local bar to taste some typical local pintxos. Take the opportunity to chat with your guide, and ask for recommendations for the rest of your time in Barcelona.