Simandou, Africa’s largest mining and related infrastructure project, has reached a critical stage as construction and commissioning accelerate across its mines, railway, and port systems in Guinea. The vast development, which integrates two large iron ore mines with more than 600 km of trans-Guinean railway and new port facilities, is positioned to reshape the country’s economy and the global iron ore market once fully operational.
The project is being developed through a dual structure involving SimFer, a subsidiary of Rio Tinto, and the Winning Consortium Simandou (WCS). Together, the two partnerships will operate two integrated mines and a shared rail and port system capable of exporting up to 120 million tonnes of iron ore annually at full capacity, evenly split between SimFer and WCS. SimFer holds rights to the southern blocks of the project, Blocks 3 and 4, while WCS controls the northern Blocks 1 and 2.
SimFer is jointly owned by the Government of the Republic of Guinea and SimFer Jersey Limited, which in turn is owned by Rio Tinto and Chalco Iron Ore Holdings, a Chinalco-led joint venture that includes major Chinese state-owned enterprises such as China Baowu Steel Group. WCS is a strategic alliance led by the Singapore-headquartered Winning International Group, alongside China’s Weiqiao Aluminium and Baowu Resources, and is also co-developing the project with the Guinean government and its partners, including Rio Tinto.
Rio Tinto is responsible for developing Blocks 3 and 4 through the SimFer joint venture. Current inferred estimates for SimFer indicate ore reserves of around 1.5 billion tonnes and mineral resources of approximately 1.3 billion tonnes, underlining Simandou’s status as one of the world’s most significant undeveloped iron ore deposits.
Both SimFer and WCS are constructing mines on their respective blocks while jointly building the shared rail line and port infrastructure. This common infrastructure will be owned and operated by La Compagnie du Trans-Guinéen, a special-purpose company established for the project. SimFer is also responsible for building its mine and associated infrastructure, a 78 km rail spur connecting to the main railway, and its own trans-shipment vessel port facilities.
Testing and commissioning of the rail and port infrastructure are already underway. According to Rio Tinto, both SimFer and WCS have begun transporting ore from their respective mines to the port via the trans-Guinean rail line as part of these trials. Under current plans, SimFer will initially use port facilities built by WCS until its own trans-shipment vessel port is completed and commissioned in 2027, after which CTG will take over operation of the shared infrastructure.
The project achieved a key milestone in 2025 with the production of first ore, including SimFer transporting its first shipment in October during testing and commissioning. Key timelines outlined by Rio Tinto include completion of the SimFer rail spur and the main rail line constructed by WCS in 2026, initial shipping through the WCS barge port, commissioning of SimFer’s trans-shipment vessels in 2027, and SimFer’s mine reaching a production rate of 60 million tonnes per annum by 2028.
CTG, jointly owned by the Government of Guinea, SimFer, and WCS, will operate the shared infrastructure, including a 670 km railway and a new deep-water port designed to move iron ore from the interior to the coast. The system includes 12 stations, more than 200 bridges, and four tunnels, making it one of the most ambitious infrastructure projects ever undertaken in West Africa.
Rio Tinto says the Guinean government has mandated ambitious delivery timelines to ensure the project has a major economic impact. Around 25,000 employees and contractors are currently working across the SimFer scope of work, with 82% of them being Guinean nationals. The company and its partners have committed to an accelerated schedule while maintaining internationally recognised standards in safety, governance, social well-being, and environmental stewardship.
At the official opening of the Simandou project held in November last year at the port in Forécariah prefecture, Rio Tinto chief executive Simon Trott described the progress achieved so far as the result of close cooperation among partners. He said the project is unlocking an exceptional new source of high-grade iron ore needed for low-carbon steelmaking, while strengthening Rio Tinto’s global iron ore portfolio alongside its operations in Australia and Canada.
Trott emphasised that Simandou represents more than a mining venture, calling it a catalyst for development that is already generating jobs, infrastructure, and new opportunities in Guinea. He said the project is expected to play a significant role in growing the country’s economy and positioning it for participation in a low-carbon future.
He also described Simandou as a game-changer in terms of partnership models, marking the first time an international consortium of this scale has come together to deliver a project of such size and complexity at this pace. Despite the challenges, Trott said working side by side has strengthened relationships among partners and laid the foundation for Rio Tinto’s future approach to large-scale developments, anchored in long-term commitment to Guinea, its communities, and its economic future.
