The Soo Express was a standard passenger consist of the era: engine, baggage car, mail car, colonist car, second-class coach, first-class coach, dining car, and sleeping car -- a Pullman, as they were known. The accounts of what happened next are contradictory, pieced together from a small number of survivors and newspaper reports that spread conflicting details across North America in the days that followed. What is clear is that the second-class coach became detached from the front of the train on the approach to the bridge. Momentum drove it forward into the iron structure, which cleaved the wooden car into two pieces and set it ablaze. The first-class coach was the next to fall, breaking cleanly through the ice and sinking deep into the river. The dining car followed, though it did not sink as far, sparing the kitchen end. The sleeping car toppled sideways into a snowbank, which cushioned its fall and likely saved every passenger aboard.

The pattern of death defied intuition. The second-class coach, packed with passengers and torn apart by the bridge, was devastated by fire. Passengers in the half that remained above the river were trapped in burning wreckage, and those who jumped or fell landed on the ice below. But the first-class coach, which suffered less direct impact and fell into the river relatively intact, had the highest death rate of any car on the train. Passengers who escaped through windows or doors found themselves in freezing water beneath a ceiling of ice they could not break through. Only one passenger from the first-class coach is reported to have survived. The sleeping car, by contrast, produced many injuries but zero deaths -- its tumble into the snowbank was violent but not lethal. The crash's geography compounded the tragedy: the nearest town, Nairn, lay some distance to the east, denying survivors any immediate source of aid, warmth, or medical attention.

Rescue began immediately, led by crew members and passengers who were uninjured or only lightly hurt. William Dundas, the mail clerk, survived from his relatively protected position near the front of the train and began pulling people from wreckage. The brakeman from the second-class coach, who had been thrown clear onto the ice in what can only be described as a miracle, joined the effort. But the rescuers faced an impossible situation: survivors were divided by the icy river, and the bridge itself was clogged with burning debris. Someone had to reach Nairn. The brakeman and several passengers undertook the trek through deep snow to summon help. Among the survivors was William J. Bell, a local lumber baron and industrialist who was seriously injured but lived. Downstream in Espanola, the Spanish River Pulp and Paper Company dam operators raised the water level at the bridge by four feet, slowing the current to help recover bodies from the crash site.

The investigation that followed produced suspicion but no certainty. The most widely accepted theory is that poor track conditions combined with excessive speed on the curve leading to the bridge caused the derailment. Locals knew the stretch of track in the lead-up to the bridge suffered from spreading and breaking -- the rails shifting apart under stress -- but the train crew may not have been aware of the problem. The death toll itself remained disputed: early estimates began around 40, and official counts settled at 43 or 44, though some reports pushed the number as high as 70. The confusion stemmed from the era's record-keeping, the destruction of the coaches, and the difficulty of recovering all victims from the frozen river. No external witnesses saw the crash, and the relatively small number of survivors left many questions permanently unanswered.

The Spanish River crossing remained a trouble spot for rail operations long after 1910. The railway corridor through this part of northern Ontario follows terrain that is rough, rocky, and hard on infrastructure. Over a century later, in 2015, a Huron Central Railway freight train derailed near the town of Spanish, not far from the site of the 1910 disaster. An investigation by the Transportation Safety Board of Canada found that "a large number of rail joint defects were allowed to remain in service" -- language that echoes the suspected cause of the Soo Express tragedy. The Spanish River bridge where 43 people died on that January afternoon is gone now, replaced by modern infrastructure, but the river still runs cold and dark beneath the tracks, and the curve still bends through the same northern Ontario bush where an express train once lost its grip on the rails.