Three days is the ideal length for a first visit to Monaco. It is long enough to see the headline sights without rushing, and short enough that you will not run out of things to do. The principality is only about two square kilometres, but it is steep, so the plan below groups sights by district to keep the climbing sensible. Each day has a morning, an afternoon and a flexible evening, and you can swap the days around depending on the weather.
Day one: the Rock
Start early in Monaco-Ville, the old town on the Rock, while the lanes are quiet. Take the public lifts or the stairs from the port, walk to the Palace Square and watch the Changing of the Guard at 11:55, which is free and short. Walk down to Monaco Cathedral, where Princess Grace and Prince Rainier III are buried, remembering to cover your shoulders, then wander through the Saint-Martin Gardens to the statue of Prince Albert I and the sea views. The Oceanographic Museum is the natural afternoon anchor: book a dated ticket, head to the aquarium first, and finish on the roof terrace. Lunch in the old town is pleasant but pricey, so many visitors take a picnic to the gardens instead. Dinner can be in La Condamine, down at sea level, where the evening atmosphere around the Place d'Armes is lively and more affordable.
Day two: Monte-Carlo and the harbour
Begin at Casino Square, which is quieter in the morning. The Casino atrium is free to enter, and a heritage visit gives you the story of the building and the Opéra next door. Walk the Grand Prix route on foot, either on a guided circuit walk or by yourself, from the Sainte-Dévote corner up to the Casino, around the hairpin and down towards the tunnel and the port. Stop at the small Sainte-Dévote church, then spend the early afternoon in La Condamine: the market hall for lunch, with barbagiuan, socca and pissaladière, and a stroll around Port Hercule to look at the yachts. If you have energy, the Prince's Car Collection is close to the harbour and is a good rainy-day option. In the evening, dress up for the Casino gaming rooms, which require photo ID and smart clothes, or simply have a drink on a terrace on Casino Square and watch the sports cars arrive.
Day three: the green and seafront side, plus the coast
Spend the morning at the Exotic Garden, high above the harbour, for cacti terraces and the best views of the principality, and consider the guided cave tour if you do not mind stairs. In the afternoon, head to Larvotto: the Japanese Garden is a free and tranquil stop, and Larvotto Beach is the easiest place to swim between late spring and early autumn. Alternatively, take a half-day small-group trip to the hilltop village of Èze, or ride the train along the coast to Nice or Menton. If you prefer to stay put, the Nouveau Musée National de Monaco makes a quiet cultural hour, and the Fontvieille Park and Princess Grace Rose Garden are calm places to end the trip.
Getting around
Walk where you can, and use the lifts and escalators that link the harbour, the Rock and Monte-Carlo. Local buses run through the districts, and a hop-on hop-off bus is an easy way to cover the whole principality in about an hour if you want commentary and a rest for your legs. Taxis are plentiful, and the railway station is close to the harbour and Monte-Carlo, so you do not need a car. Wear comfortable shoes with grip, since some streets are steep and the old town is cobbled.
Tips for pacing
Do the outdoor sights in the morning and the museums in the afternoon in hot weather, and reverse the order on cool, clear days when the light is good for views. Book very little in advance: the Oceanographic Museum, the Exotic Garden's cave visit and a guided circuit walk are the only things that really benefit from a reservation. Leave one evening unplanned, because the best moments in Monaco are often unplanned, such as a sunset from the Saint-Martin Gardens or a late coffee beside the harbour. Finally, base yourself in the part of Monaco that suits your plan: the port or La Condamine for walkability, Casino Square for glamour, Larvotto for the sea, or Fontvieille for calm.
