... besides many stores, restaurants and bars this street is also lined with some buildings of the modernista architecture, like the Casa Mila, Casa Batllo (also by A. Gaudi) and next door Casa Amatller (by Josep Puig i Cadafalch).
Palau Güell ...
... is the only Gaudi house completely open to the public. It was built in the late 1880s. Inside of the house it was forbidden to take any pictures, therefore I've got just a couple of pictures from the rooftop an it's colorful chimney pots.
See also: AntoniGaudi.net