The barrios of Puerto Rico are the primary legal divisions of the seventy-eight municipalities of Puerto Rico. Each of the 78 municipios is divided into geographical sections called barrios (English: wards).
The history of the creation of the barrios of Puerto Rico can be traced to the 19th century (1800s) when historical documents start mentioning them. Historians have speculated their creation may have been related to the Puerto Rican representation at the Cádiz Cortes. The names of barrios in Puerto Rico come from various sources, mostly from Spanish or Indian origin. One barrio in each municipality (except Florida, Ponce, and San Juan) is identified as the barrio-pueblo, the area that represented the seat of the government at the time Puerto Rico formalized the municipio and barrio boundaries in the late 1940s. From time to time barrios are created, broken up, or merged.
The United States Census Bureau recognizes 901 barrios in Puerto Rico. As components of each municipality, each municipality has one or more barrios. Every municipality has at least one barrio called barrio Pueblo which is home to the largest urban area of the municipality, and the political seat of the municipality. Most municipalities have a single barrio named barrio Pueblo while others, most prominently the larger municipalities like the municipality of Ponce, may have a barrio Pueblo that is made of several barrios. Florida is the municipality with the least number of barrios, while Ponce, at 31, has the largest number. The US Census Bureau further breaks down some barrios in Puerto Rico into sub-barrios. An example is barrio Segundo in Ponce which consists of sub-barrios "Clausells" and "Baldorioty de Castro" (commonly shortened to just "Baldorioty"). With over 24 square miles, barrio Lapa in the northeast area of the municipality of Salinas, has the largest territorial area of any barrio in Puerto Rico. It is so large, it is actually larger than 10 of Puerto Rico's municipalities.