Monaco ⁱ/ˈmɒnəkoʊ/, officially the Principality of Monaco (French: Principauté de Monaco; Monégasque: Principatu de Múnegu; Italian: Principato di Monaco; Occitan: Principat de Mónegue), is a sovereign city state, located on the French Riviera in Western Europe. Bordered by France on three sides, with one side bordering the Mediterranean Sea, its center is about 16 km (9.9 mi) from Italy, and is only 15 km (9.3 mi) north east of Nice, France. It has an area of 1.98 km² (0.76 sq mi), and a population of 35,986, making Monaco the second smallest and the most densely populated country in the world. Monaco has a land border of only 4.4 km (2.7 mi), a coastline of 4.1 km (2.5 mi), and a width that varies between 1.7 km (1.1 mi) and 349 metres (382 yards). The highest point in the country is a narrow pathway named Chemin des Révoires on the slopes of Mont Agel, in the Les Révoires district, which is 161 metres (528 feet) above sea level. Monaco's most populated Quartier is Monte Carlo, and the most populated Ward is Larvotto/Bas Moulins. After a recent expansion of Port Hercules, Monaco's total area is 2.05 km² (0.79 sq mi), with new plans to extend the district of Fontvieille, with land reclaimed from the Mediterranean Sea.

The Rock of Monaco (French: Rocher de Monaco) is a 141 meter (459 foot) tall monolith on the Mediterranean coast of the Principality of Monaco.

The Rock has been a coveted possession from the beginning of the ancient Massilian colony of Monoïkos (Greek: Μόνοικος), named for the Ligurian tribes who occupied the area and vied for control of it; even earlier, it was a shelter for primitive populations. The Rock of Monaco was also the first conquest of the Grimaldi dynasty, the rulers of the country for more than 700 years, founded when the Guelf Francesco Grimaldi disguised himself as a Franciscan monk in order to gain entry to the city and open the gates for his soldiers.

Today, the Rock is in the oldest of Monaco's four quarters, Monaco-Ville, which is also the location of Old Town, the oldest part of the city. This is not far from the Prince's Palace (French: Le Palais Princier), home of the current monarch, Albert II and the princely family, the Cathedral, the Oceanographic Museum of Monaco. The Rock of Monaco is a popular attraction where tourists view the palace or the changing of the guards.