Concierge.com's insider take:
The sweeping vistas, pink sunsets, and medieval towns along the Grande Corniche were romanticized in Hitchcock's To Catch a Thief. They are all still there and still worth the trip. There are actually three Corniches: the Grande Corniche, the Corniche Moyenne, and the Corniche Inférieure. All connect Nice to Monaco (actually to Menton, but the road after Monaco is anticlimactic), running parallel through, or above, the same towns. A lovely drive would start on the Promenade des Anglais in Nice and follow the Corniche Inférieure (marked N98 on maps) along the shore to Monaco. You'll pass through Villefranche-sur-Mer, a fishing village where the Rolling Stones hung out in the 1970s and that today feels like a less spoiled, more family-friendly version of St. Tropez. After the mansions in the hills of St.-Jean-Cap-Ferrat comes the shock of the high rises and marble shopping malls of Monte Carlo. The route back on the Corniche Moyenne, marked as the N7 or the D45, hugs the cliffs and delivers plenty of dramatic vistas, as well as the cliff-top village of Eze. The Grande Corniche is laughably hard to find, on a map or in either Nice or Monaco; officially, it's the D2564, a tiny departementale road.> Take the Corniche Moyenne and look for tiny signs that take you onto the Grande Corniche for a few high-altitude viewsand plan your return to coincide with sunset.