Saint-Pierre is the third-largest commune in Réunion, a French overseas department and region located in the Indian Ocean east of Madagascar. The city is situated on the southwest coast of the island and serves as an important administrative and economic center for the region.
Saint-Pierre functions as the headquarters of the French Southern and Antarctic Lands, making it a significant administrative hub beyond its role as a major commune. This designation reflects the city's importance in French colonial and territorial governance in the Indian Ocean.