The calculated distance (air line) between Rio de Janeiro and Barra do Piraí is approximately 51 miles respectively 82 kilometers.
By car or train, the actual journey to Barra do Piraí is certainly longer, as only the direct route (as the crow flies) between Rio de Janeiro and Barra do Piraí has been calculated here.
Air line (approximately)
82 kilometers
44 nautical miles