San Juan is subdivided into 18 districts (barrios), 16 of which fall within the former (until 1951) municipio of Rio Piedras. 8 districts (barrios) are further subdivided into subsectors (sub-barrios), including both districts of the former municipio of San Juan:
Contents
Former municipio of Río Piedras
Former municipio of San Juan (until 1951)
collective terms (former “barrios”)
References
Subdivisions of San Juan, Puerto Rico Wikipedia(Text) CC BY-SA