The route is a main traffic artery in East Africa, connecting the port and airport of Dar es Salaam to the Tanzanian inland and neighbouring countries.
BAM and Danish partner Per Aarsleff renovated the Tanzam highway between Iyovia and Mafinga in a €134m (£115m) contract.
In addition to rehabilitating and strengthening the carriageway, the contract involved building paved shoulders and climbing lanes to make the road safer. Other traffic safety improvement measures were included in towns, villages and hazard spots.
The scope of work also included the construction of a weighbridge station and ancillary tasks such as signage, road lining and guardrails. The project was financially supported by the Danish government.