I recently came accross the EU Civitas project about superblocks in Spain. The project’s synopsis is briefly summarized in this video, while the evaluation report can be accessed under this link.

The project intends to bundle through traffic flows and create zones for slow traffic and pedestrians not only in the city center but also distributed around the city. This initiative is targeted at strongly planned cities, strongly built after the industrialization in Europe and in the US and aims to create superblock zones. Within these zones, motorized traffic moves slowly (e.g. < 10km/h), the pathways are wide or cover the whole street, parking lots are put underground and business utilization of ground floor location is favored.

In the Guardian article they used the following graph to illustrate it

When successfully implemented, this superblocks can, as a measure for existing cities, significantly reduce NOx and CO2 emissions while elevating the quality of life significantly.