The Metropolitan Cathedral of Saint Sebastian (Portuguese: Catedral Metropolitana de São Sebastião) better known as the Metropolitan Cathedral of Rio de Janeiro (Catedral Metropolitana do Rio de Janeiro) or as the Cathedral of St. Sebastian of Rio de Janeiro (Catedral de São Sebastião do Rio de Janeiro), is the seat of the Roman Catholic Archdiocese of São Sebastião do Rio de Janeiro. The cathedral is the See of the Metropolitan Archbishops of the city of Rio de Janeiro, Brazil. The church is dedicated to Saint Sebastian, the patron saint of Rio de Janeiro.
The cathedral was designed by Edgar de Oliveira da Fonseca in a modern style based on Mayan architectural style of pyramids. The current cathedral was built between 1964 and 1979 and replaced as seat of the Archdiocese a series of churches that had served as cathedrals since 1676, the most recent and notable of those being the Church of Our Lady of Mount Carmel of the Ancient See, now known as the Old Cathedral, built in the 18th century, and that had been declared Rio's cathedral in the early 19th century.