In many cities, convention holds that there's a lane for walking and a lane for standing on the escalator. But human systems engineers suggest this isn't the most efficient option for the system.
Huge progress has been made, but safety issues and environmental concerns mean plans are still up in the air.
Over a third of pupils in the Gauteng province still travel more than five kilometres to school.
Cities are expanding upwards and downwards, as well as outwards. With urban density also increasing, moving people efficiently around the city, often using ageing infrastructure, is quite a challenge.
The development of suburban infrastructure depends on political, technical and financial priorities. A train derailment in an Italian suburb has highlighted the need to retrofit infrastructure.
New York soon may charge a fee to drive into central Manhattan as a way of reducing traffic and raising funds for public transit. An urban scholar says this step is overdue in the United States.
For Melbourne drivers who comfort themselves with the thought that traffic congestion is worse in Sydney, sorry but new analysis shows overall delays are similar, but some commutes are especially bad.
All it takes is data ... lots of data.
Data on housing supply in Australia's capital shows that while it's increasing in areas with lots of jobs, house prices are too high for those who might want to move for work.
Bike lanes in South Africa were meant to encourage commuter cycling and ease congestion but in Johannesburg the initiative garnered more outrage than support.
The government knows the system is a shambles – but refuses to admit that rail privatisation has failed.