It would be difficult to imagine a more elegant architectural relic of the late-18thC industry than Nicolas Ledoux’s unfinished Saline Royale (Royal Saltworks) at Arc-et-Senans. The plan was to build an entire town arranged in concentric circles around the pivotal Director’s Residence, but only the central axis, with the classical overseer’s house flanked by salt halls, and a semi-circle of outbuildings, was completed.