On June 21, 2001, BHP Iron Ore set the record for the longest and heaviest freight train ever. 

The train was 4.5 miles (7.3 kilometres) long and transported 82,000 metric tons of iron ore between the Yandi mine and Port Hedland in the Pilbara region of Western Australia.

It was made up of 682 wagons, which were all powered by eight General Electric AC6000CW diesel locomotives. 

Together, they pulled a staggering gross weight of 99,734 metric tons (about 219.8 million pounds) - the equivalent of approximately 402 Statue of Liberty statues.

Mike Darby, BHP Iron Ore's Vice-President at the time, said: “It was an opportunity to push the technology to the maximum.” 

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The train’s journey covered 171 miles (275km) along the Mount Newman line, all under the watchful eye of a single driver. The locomotives were strategically placed throughout the train in pairs and single units.

This was done to make sure that traction and braking forces were optimised through advanced Locotrol radio communications.

However, the train ran into an issue when one of the devices that connected the wagons malfunctioned.

It forced the train to stop for 4 hours and 40 minutes while repairs were made. 

In total, the journey took 10 hours and 4 minutes to complete.

BHP’s Western Australia Iron Ore President at the time, Graeme Hunt, said: “This was a world-class achievement that demonstrated BHP's commitment to innovation and excellence.” 

The record surpassed BHP’s previous heaviest train record set in 1996. The train is still operational today, regularly transporting iron ore from BHP’s mines to Port Hedland, although not on the same scale.

BHP regularly moves iron ore with trains that are 1.5 miles (2.4km) long and have 264 wagons.