At Plaça Gran in Granollers, on a stone platform, fifteen columns rise up, covered by a four-sided roof with the edges covered with green glazed tiles. This Porxada or Portico, the most emblematic monument of Granollers, was built between 1586 and 1587 as a corn exchange. Today it has become the nerve centre of the city.

The initial project has been attributed to the master builder, Bartomeu Brufalt, and cost 520 Barcelonan pounds, according to the contract with the university of Granollers. Initially it was used during the agricultural market to protect the wheat that was sold here. In 1872, it was enclosed with grilles and stalls were built inside. It served its function as a general market until 1938, when a bombardment by the Francoist air force left the Porxada in ruins. After the war, in 1939, it was rebuilt without grilles or the stalls, leaving the columns open as they would have been when it was designed.

On the south-western corner of the Porxada, opposite the Granollers Town Hall, we find the Pedra de l’Encant (Stone of the Auction), a block of red sandstone which was undoubtedly used for conducting public sales (encants or auctions) of agriculture products and livestock. Legend says that this stone was carried to the Porxada by a flood and that there will be another flood that will carry it away.