São João da Fronteira (Portuguese meaning "Saint John of the frontier") is a municipality in the western part of the state of Piauí in Brazil. The population is 6,064 (2020 est.) in an area of .Instituto Brasileiro de Geografia e Estatística The elevation is 458 m.
The municipality contains part of the Serra da Ibiapaba Environmental Protection Area, created in 1996.
References
External links http://www.citybrazil.com.br/pi/sjoaofronteira/