Barri Gòtic

The Barri Gòtic is the "old town". It was once defined by a 4th century late-Roman city wall, of which just a few segments still exist. Most of the present medieval buildings date from the 14th and 15th centuries, a peak of Barcelona's (and Catalonia's) independent prosperity before being swallowed up by the Castilian center. Now it's a mostly pedestrian warren of narrow streets (though watch out for mopeds!), filled with restaurants and little stores, plazas, churches, and cafés.

Click on the small pictures to see larger ones.

Plaça Reial

The Plaça Reial dates from 1850, on the site of the old Capuchin convent. The lamposts, or fanals, were designed in 1878 by the young Antoni Gaudí.

To the left and right, entrances to the square, and below, a panorama of the square itself. Just to the right in the image, down a short street, are Las Ramblas.
(This is one of my less-successful panoramas, requiring too much image warping, presumably because my hand-held technique was not consistent enough.)

La Seu

Barcelona's cathedral was begun in 1298 and completed in 1448, except for the façade, which wasn't done until in the 1880's, though in a compatibly Gothic style. As is common, the site was that of a Moorish mosque, and before that, a Roman temple.
Perhaps the cathedral's most notable and attractive feature is the 14th-century cloister, with garden, palm trees, fountain, and even a flock of white geese!
Some fun buildings just by the cathedral. Just to the right, that gargoyle looks like one of Hannibal's elephants. And in fact Barcelona was founded by the Carthaginians around 230 BC, right here around the cathedral site. 

Santa María del Pi

Pleasant little squares with cafés and occasional markets, surrounding the 14th-century Eglésia de Santa María del Pi, named after a pine tree that used to stand here. The church is in the very open Catalan-Gothic style, with some great stained glass.

Plaça del Rei

On the left the square itself, once the courtyard of the palace of the counts of Barcelona. On these steps stood King Ferdinand and Queen Isabella to greet Columbus on his return from America. In the hall behind, the Saló del Tinell, met the Spanish Inquisition.
On the right, on the outside of the square, one can see the remains of the Roman wall on the bottom. (The bigger blocks.)

Carrer de Montcada

This street is famous for its late-medieval mansions, one of which houses the Museu Picasso, which I didn't visit, due to the crowds. Here is the Palau Dalmases, a later 17th century Baroque example, with the typical flagstone courtyard and exterior staircase.