Pizzeria Trianon is a long-standing pizzeria in Barcelona that has been serving delicious pizzas since 1920. They are known for their thin-crust pizzas with a wide range of toppings to choose from. The menu includes classics like Margherita and Pepperoni, as well as unique creations like the Trianon Special with ham, mushrooms, and artichokes. The restaurant has a retro vibe and is a favorite among locals and tourists alike.