A4400 road

The A4400 (or Inner Ring Road or Queensway) was a main road in Birmingham, United Kingdom that previously formed a ring around the city centre. Junctions on the road were largely grade separated, with pedestrians kept physically separate from vehicular traffic and most junctions allowing vehicles staying on the road to pass over or under those using the junction. It is now widely regarded as one of the classic urban planning blunders of the 20th century.

Although seen as a revolutionary improvement when the first section opened in 1960, the 'Concrete Collar', as it became known, was viewed by council planners as an impenetrable barrier for the expansion of the city centre. In particular, it became unpopular with pedestrians, who were required to use subways at the roundabouts, an unpopular route due to fear of crime. However, some users cite the efficiency of grade separated design.

Since 1988, the city council has sought to recreate links between the city centre and the neighbouring areas, enlarging the city centre and improving the pedestrian environment across the city, with an emphasis on shifting vehicular movements out to the Middle Ring Road. Controversially, pedestrian crossings are replacing underpasses.