The freak wave that wiped out half the grid in 1950 Monaco Grand Prix

Racing along Monte-Carlo’s waterside has provided some of Formula 1’s most idyllic images, but the circuit’s coastal location proved disastrous in 1950 when an unexpected wave crashed over the harbour wall during the Monaco Grand Prix

In one of F1’s strangest twists, the surge triggered a crash involving almost half of the grid on the opening lap, and the wreckage caught more drivers out on lap two, when they sped into the blind Tabac corner, unaware of the cars littering the track ahead.

But in contrast to the fortunes of his rivals, Juan Manuel Fangio threaded his way through the mayhem and away into the lead thanks to an almost supernatural reading of the situation that forms a cornerstone of his legend.

This is the story of the first, and possible most unusual world championship-class Monaco Grand Prix.

It was 75 years ago today – May 21 – that Monte Carlo welcomed Formula 1 cars for the second round of the inaugural world championship, which also marked the series debut of Scuderia Ferrari, which had missed the opening round at Silverstone.

Fangio started from pole position, with his Alfa Romeo team-mate Giuseppe “Nino” Farina in second. As racing got underway, the Argentine kept his lead as the grid of 19 starters began to tackle the then 3.180 km (1.976 mile) street circuit.

However, as they navigated the first corners, a huge wave washed over the harbour wall and flooded the track at Tabac. Unsighted by the high walls at the point of the circuit the grid raced into the left hander. Fangio sailed through in his Alfa Romeo 158 but team-mate Giuseppe Farina spun on the newly-formed lake, sliding into a set of stone steps and bouncing back onto the track.

Ferrari’s Luigi Villoresi made it through but Alfa’s Luigi Fagioli also spun and hit Farina; Froilan Gonzalez’s Maserati hit them both and split them apart, widening the crash scene. Into that piled many of the following cars, forcing nine into retirement.

Archive footage shows cars being pushed off the circuit with litres of fluid pouring out, as marshals and drivers attempted to clear the route. But the scale of the crash meant that there was just a car’s width of clear track when Fangio arrived on the second lap, and just a single marshal waving a yellow flag at the entrance to Tabac, unseen by many of the competitors.

As he accelerated out of the previous chicane, Fangio suddenly realised that the spectators were looking towards Tabac rather than the approaching leaders. His mind flashed to a similar first-lap pile-up at Monaco in 1936 — he had been looking at a photograph of the crash the day before.

“I braked hard and stopped, just before all the wreckage,” Fangio told Motor Sport‘s Nigel Roebuck. “People said that I must have had a sixth sense, but it wasn’t like that, really – I was lucky.

“There had been a similar accident in 1936, and I happened to see a photograph of it the day before the race. On the second lap, as I came out of the chicane before Tabac, I was aware of something different with the crowd – a different colour. And I realised that, instead of seeing their faces, I was seeing the backs of their heads. I was leading the race, but they weren’t watching me – so something down the road was more interesting. And I remembered that photo…”