Three roads, and what makes a driver switch
The Princely Government names them itself: the Basse Corniche along the coast, the Moyenne Corniche D6007, the Grande Corniche D2564. The first, numbered D6098 on the French side, leaves the airport along the Promenade des Anglais, runs through Villefranche-sur-Mer, Beaulieu-sur-Mer and Cap-d’Ail, then crosses the border on boulevard Charles III. The fourth option is the motorway: junction 56 heading France to Italy, junction 58 heading back.
The choice is not a matter of taste. A morning arrival that lands as the coast road fills up does not take the same line as a 22:00 arrival. The Princely Government publishes 22 km and 25 minutes by motorway from the airport; our grid holds 30 km and 35 minutes, measured from Terminal 2 to an address rather than to a border. Both figures are right. They do not measure the same thing.
What the coach and the helicopter really do
The Zou number 80 coach exists, it is cheap, and its timetable states plainly what it does. Departures from Terminal 2 between 08:30 and 22:00, €21.40 a ticket bought in advance, and 42 to 55 minutes to Place d’Armes depending on the run. None takes 30 minutes. The timetable also prints a useful caveat: direct to Monaco only if nobody alights at Menton or Roquebrune-Cap-Martin.
The return leg is the real subject. The last departure towards the airport leaves Larvotto at 20:05 and Place d’Armes at 20:15, reaching Terminal 2 at 20:48. After that there is no coach.
The helicopter takes 7 minutes from Fontvieille heliport, every 30 minutes, from €195 per person. It stops at nightfall. For a 23:00 flight the question does not arise.
A number plate can close a street
The government guide is blunt: access to the Rock district is closed to all vehicles except those registered in the Principality or in the Alpes-Maritimes. A car registered in the Var, or hired abroad, does not go up without a waiver from the town hall.
The same text sets the dimensions. Beyond 18.75 m long, 2.60 m wide or 4.30 m high, traffic is banned, and anything over 7.5 tonnes gross is banned across the territory apart from the access roads to Fontvieille and Larvotto. A saloon and a passenger van pass. This is the kind of detail that gets checked before the job, not at the barrier.