Monaco, officially the Principality of Monaco, is a sovereign city-state, located on the French Riviera in Western Europe. It is bordered by France on three sides; one side borders the Mediterranean Sea. It has an area of 2.02 km², and a population of 36,371, making Monaco the second smallest, and the most densely populated, country in the world. Monaco has a land border of only 4.4 km, a coastline of 4.1 km, and a width that varies between 1,700 and 349 m. 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 above sea level. Monaco's most populous Quartier is Monte Carlo, and the most populous Ward is Larvotto/Bas Moulins. Monaco is known for its land reclamation, which has increased its size by an estimated 20%.
Monaco is a principality governed under a form of constitutional monarchy, with Prince Albert II as head of state. Even though Prince Albert II is a constitutional monarch, he still has immense political power. The House of Grimaldi have ruled Monaco, with brief interruptions, since 1297. The official language is French, but Monégasque, Italian, and English are widely spoken and understood. The state's sovereignty was officially recognized by the Franco-Monegasque Treaty of 1861, with Monaco becoming a full United Nations voting member in 1993. Despite Monaco's independence and separate foreign policy, its defence is the responsibility of France. However, Monaco does maintain two small military units.