Police concerned about the strong currents in the River Cherwell had earlier shut the bridge to stop inebriated students jumping in, a May Day pastime that has also become a matter of concern to local authorities and welfare officers.
The heavy police presence failed to discourage a motley assortment of bedraggled ball-goers, bemused tourists and early rising locals from assembling before first light.
There were fears that some would try to force the police cordon but only one dinner-jacketed student toyed briefly with the idea of a dash through the lines until one of his group shouted: "Who wants to jump in the river, anyway. Let's go to the pub."
Photograph: Tom PilstonReuse content