The calculated distance (air line) between Belo Horizonte and Barra Mansa is approximately 182 miles respectively 293 kilometers.
By car or train, the actual journey to Barra Mansa is certainly longer, as only the direct route (as the crow flies) between Belo Horizonte and Barra Mansa has been calculated here.
Air line (approximately)
293 kilometers
158 nautical miles