A superblock or super-block is an area of urban land bounded by arterial roads that is the size of multiple typically-sized city blocks. Within the superblock, the local road network, if any, is designed to serve local needs only. From Wikipedia
The superblock concept has been applied retroactively in Barcelona's La Ribera and Gràcia districts, which both have a medieval street network with narrow and irregular streets, since 1993. In these two cases it resulted in an increase of journeys on foot (over 10%) and by bicycle (>15%) and in a higher level of commercial and service activity. From Wikipedia
Modern cities are designed for cars. But the city of Barcelona is testing out an urban design trick that can give cities back to pedestrians.