Race of Two Worlds

The Race of Two Worlds (Trofeo dei Due Mondi in Italian), also known as the 500 Miglia di Monza (500 Miles of Monza), was an automobile race held at the Autodromo Nazionale Monza, Italy in 1957 and again in 1958. It was intended as an exhibition event, allowing American teams from the United States Auto Club (USAC) National Championship to compete directly against teams from the Formula One World Championship based in Europe. The two types of cars competed on the banked oval at Monza which had been completed in 1955. Due to the similarity to the Indianapolis Motor Speedway, where the USAC teams ran the Indianapolis 500, the event earned the nickname Monzanapolis.

American drivers and teams won the event in both the years in which it was run. Jimmy Bryan won the 1957 event, and Jim Rathmann swept the 1958 race. Although some Formula One teams did participate and even built special cars specifically for the event, several withdrew over safety concerns. Continued concern over the speeds on the track and the cost of the event led to the race being canceled after the 1958 running.

In 1954, redevelopment of the Autodromo Nazionale Monza circuit began for the first time since 1948, concentrating on rebuilding the oval portion of the track which had been abandoned during World War II. The 4.5 kilometres (2.8 mi) banked oval, which had last been used in 1933, was dismantled. The southern Sud Alta Velocita corner was relocated, moving it northward by several meters, shortening the lap distance length to 4.25 km (2.64 mi). Both banked corners were rebuilt on a curving gradient which reached 80 degrees, replacing the flat banking which had been previously used. The reconstruction was completed in August 1955, in time for the Formula One Italian Grand Prix, which combined the new oval with the Monza road course for a full 9.8 km (6.1 mi).

The following year, Giuseppe Bacciagaluppi, then president of the Automobile Club of Milan and chairman of the Autodromo Nazionale Monza, invited Duane Carter, competition director of USAC, to attend the second running of the Italian Grand Prix on the new circuit. The two discussed the similarities between Monza's new oval and the Indianapolis Motor Speedway, which also held a round of the 1957 Formula One season, the Indianapolis 500. Although the 500 counted as part of the championship, only a few Europeans attempted to participate in the event since the formation of the World Championship. Ferrari's Alberto Ascari in 1952 was the only European competitor to actually qualify for the race. Bacciagaluppi and Carter believed that an oval race held in Europe instead of the United States could attract Formula One teams, and USAC and the Automobile Club of Italy began work on making such an event possible.

A race was scheduled for June 1957, running just the 4.25 km oval at Monza. Volunteering USAC teams were to be transported from the United States, while Formula One teams were also free to participate if they chose. In preparation, Firestone Tire and Rubber Company transported a USAC Kurtis Kraft–Chrysler to Monza in April 1957 in order to conduct tests on tyres made for the event. American driver Pat O'Connor completed 364 km (226 mi) on the oval, setting a best lap speed of 273 km/h (170 mph), nearly 48 km/h (30 mph) faster than lap speeds reached at Indianapolis.

The rules for the race were based on those used by USAC in North America. Engines were limited to 4,200 cubic centimetres (260 cu in) in naturally aspirated form, 2,800 cm³ (170 cu in) for supercharged engines. A USAC rolling start was also used, instead of Formula One's usual standing start. The race was planned for a distance of 500 miles (800 km), similar to the Indianapolis 500. However, unlike Indianapolis, the 500 miles would not be run continuously. Instead, three separate 63-lap heats were planned, with an hour break for repairs and rest between each heat, for a total of approximately 500 miles. The overall race winner would be determined by the driver which finished all three heats with the highest average speed. The circuit would be run in an anti-clockwise direction, the same used at Indianapolis, but opposite the direction used by Formula One at Monza.

The inaugural running of the Race of Two Worlds was scheduled for Sunday, June 29, shortly after the running of the Indianapolis 500, and a few weeks before the running of the French Grand Prix. USAC's entries in the event traveled from Indianapolis to New York City, whence they were shipped to Genoa. The drivers and personnel traveled separately from their cars, arriving by plane. The teams and equipment were then transported from Genoa to Monza, where teams began practice on Tuesday the 18th.

Fifteen cars were entered for the event. Ten cars traveled across the Atlantic from USAC, while only two teams arrived with Formula One equipment. Mario Bornigia used a privateer Ferrari, while Maserati entered their factory driver Jean Behra. The rest of the Formula One teams however chose to boycott the event. The Union des Pilotes Professionnels Internationaux (International Union of Professional Pilots), which had been formed only a few months prior, cited the dangers of the speeds able to be obtained on the Monza banking and the wear on tires posing threats to safety. A further three entries arrived from the World Sportscar Championship, thanks to the Scottish Ecurie Ecosse Jaguar team, who had just won the 24 Hours of Le Mans the weekend before.