The longest circuit ever to host a Formula 1 race was the Pescara Circuit with a lap distance of 25.8 kilometres (16.032 miles).
The track held the one and only Pescara Grand Prix in history, back in 1957. The Pole Position time, set by Juan Manuel Fangio, was 9:44.6 minutes, the same time as the Fastest Lap of the race, set by race-winner Stirling Moss.
The race was run to 18 laps, which meant a total race distance of 464.4 kilometres and a race time of 2:59.22.7 for the winner.