Green’s Dictionary of Slang

cobbles n.

the street, actual cobbles are not necessary.

[UK]R. Milward Man-Eating Typewriter 189: I swished along the cobbles.

In phrases

on the cobbles [i.e. ‘outside’ in the street]

looking for a fight.

[UK]J. Franklyn Cockney 307: ‘See you on the stones’ or ‘on the cobbles’ is a form of challenge used by boys above school-age. The expression is also employed by adults, and an extension of its application is to say: ‘They was on the cobbles all right,’ which may mean actually engaged in fisticuffs, or quarrelling violently, or even being merely bad friends.
[UK]A. Burgess Enderby Outside in Complete Enderby (2002) 366: Forked me on the cobbles and no rare-with-Worcester [i.e. mistake].
[UK] in G. Tremlett Little Legs 3: He was what we call on the cobbles, ready for a fight.
[UK]J.J. Connolly Layer Cake 45: We’ll be fuckin relics like the old bruisers having tear-ups on the cobbles.