When the last jug of buttery cream succumbs to the first jug of olive oil, there lies Provence. The northern border is easy to define; on the march from Elba to Waterloo Napoleon took the northern road, the high road, out of Provence through Sisteron, a town which for centuries has been the gateway to Provence from the county of Dauphiné. The Romans, a few years earlier than the tiny ex-emperor, marched into Provence from the east, over the mountains at La Turbie, 1500 feet above what is now Monte Carlo. Here in 6BC they erected the massive Tower of Augustus, the Trophy of the Alps-originally 165 feet of monumental stone to commemorate Rome’s invincibility. On this were inscribed the words HUC USQE ITALIA ABHINC GALLIA or ‘Hitherto Italy Henceforward Gaul’.