Constantine I  324-325 AD. AE Follis, Arles. 2.67g.

Obv: CONSTAN-TINVS AVG - Laureate head right. 
Rev: PROVIDEN-TIAE AVGG - Campgate with two turrets and one star. 
Mintmark P star AR.

RIC VII, Arles 264, rated R2.

Courtesy of yorkcoins.com, from the Killingholme Hoard.