The 14th arrondissement of Paris, officially named arrondissement de l'Observatoire, is one of the 20 arrondissements of the capital city of France. It is situated on the left bank of the River Seine, containing most of the Montparnasse district. Although today Montparnasse is best known for its skyscraper, Tour Montparnasse, as well as its major railway terminus, Gare Montparnasse, these are both actually located (partly) in the neighbouring 15th arrondissement. The district has traditionally been home to many artists as well as a Breton community, arrived at the beginning of the 20th century upon the creation of the Montparnasse railway terminus.

Montparnasse is an area in the south of Paris, France, on the left bank of the river Seine, centred at the crossroads of the Boulevard du Montparnasse and the Rue de Rennes, between the Rue de Rennes and boulevard Raspail. It is split between the 6th, 14th, and 15th arrondissements of the city. Montparnasse has been part of Paris since 1669.