The calculated distance (air line) between Thái Nguyên and Bắc Kạn is approximately 38 miles respectively 61 kilometers.
By car or train, the actual journey to Bắc Kạn is certainly longer, as only the direct route (as the crow flies) between Thái Nguyên and Bắc Kạn has been calculated here.
Air line (approximately)
61 kilometers
33 nautical miles