ring-road

It is 39 metres across the Barton Park junction cycling from Barton Park to Northway, and 46 metres going the other way, measuring the distance from the stop line to the edge of the far-side A40 traffic lane.

For this to be safely cycled by children and slower adults, someone cycling at 8mph needs to be able to get across before the red lights on the A40 go amber (since some drivers treat amber signals as green and will "amber gamble"). This needs 11 seconds southbound and 13 seconds northbound - which means inter-green periods of 13 seconds and 15 seconds.
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The speed limit on Oxford's ring-road (excepting the A34 outside Botley) should be reduced to 40mph and that should be enforced by average speed cameras. Where there are significant at-grade crossings, the speed limit should be 30mph.
This would help with road danger, congestion, community severance and barriers to walking and cycling, noise pollution, air pollution, and carbon emissions. more