Traffic congestion, closed streets because of an event, discomfort for residents.
To build acceptance for congestion charges, close attention must be paid to the local political and geographical context when designing and implementing such a scheme.
It also means private jet fliers end up flying to airports with less congestion and closer to where they are going.
The intense congestion, living in close proximity with vast crowds and the increasing percentage of elderly pilgrims, are all factors potentially magnifying this risk.
Since region 3 is within the feasible region but close to congestion, this behaviour suggests that congestion can be reached without all of the cells being active, as long as some of them are very occupied.
Any road user knows that one measure that will reduce congestion overnight is to close schools - for a variety of reasons this is probably not viable, but the half-term peace on our urban highways demonstrates that school runs contribute a huge amount of traffic.
The proposed changes are part of a Transport for London congestion charge consultation, which closes for submissions on 2 August.
And sanitation trucks, the articulated 86th Street crosstown buses and double-parked cars are a far worse source of traffic congestion than the street closing, they said.
Congestion pricing is the closest thing to a panacea that we may ever encounter for the ever-worsening traffic and pollution problems of Manhattan.
On Sunday, the Bloomberg administration put a plan into effect to reduce traffic congestion in Midtown by closing two sections of Broadway to vehicles, from 47th to 42nd Streets and 35th to 33rd Streets.
