The calculated distance (air line) between Brest and Carhaix-Plouguer is approximately 43 miles respectively 69 kilometers.
By car or train, the actual journey to Carhaix-Plouguer is certainly longer, as only the direct route (as the crow flies) between Brest and Carhaix-Plouguer has been calculated here.
Air line (approximately)
69 kilometers
37 nautical miles