The Indianapolis Motor Speedway is a motor racing circuit located in Speedway, Indiana, United States, an enclave suburb of Indianapolis, Indiana. It is the home of the Indianapolis 500 and the Brickyard 400, and formerly the home of the United States Grand Prix and the Indianapolis motorcycle Grand Prix. It is located six miles (9.7 km) west of Downtown Indianapolis.
Constructed in 1909, it is the second purpose-built, banked oval racing circuit after Brooklands and the first to be called a 'speedway'. It was the brainchild of entrepreneur Carl G. Fisher, who envisioned a proving ground for the budding automobile industry. It is the third-oldest permanent automobile race track in the world, behind Brooklands and the Milwaukee Mile. With a permanent seating capacity of 257,325, it is the highest-capacity sports venue in the world.
The track is a 2.500 mi (4.023 km) rectangular oval with dimensions that have remained essentially unchanged since its construction. It has two 0.625 mi (1.006 km) straightaways, four geometrically identical 0.250 mi (0.402 km) turns, connected by two 0.125 mi (0.201 km) short straightaways, termed "short chutes", between turns 1 and 2, and between turns 3 and 4. The turns have 9°12' banking, considered relatively flat by American standards.
A modern, FIA Grade One infield road course was completed in 2000, incorporating part of the oval, including the main stretch and the southwest turn, measuring 2.605 mi (4.192 km). In 2008, and again in 2014, the road course layout was modified to accommodate motorcycle racing, as well as to improve competition. Altogether, the current grounds have expanded from an original 320 acres (1.3 km2) on which the speedway was first built to cover an area of over 559 acres (2.3 km2). Placed on the National Register of Historic Places in 1975 and designated a National Historic Landmark in 1987, it is the only such site to be affiliated with automotive racing history.
In addition to the Indianapolis 500, the speedway also hosts NASCAR's Brickyard 400 and Pennzoil 250. From 2000 to 2007, the speedway hosted the Formula One United States Grand Prix, and from 2008 to 2015 the Moto GP. The speedway served as the venue for the opening ceremonies for the 1987 Pan American Games.
On the grounds of the speedway is the Indianapolis Motor Speedway Museum, which opened in 1956, and houses the Hall of Fame. The museum moved into its current building located in the infield in 1976. Also on the grounds is the Brickyard Crossing Golf Resort, which originally opened as the Speedway Golf Course in 1929. The golf course has 14 holes outside the track, along the backstretch, and four holes in the infield. The site is among the most visited attractions in the Indianapolis metropolitan area, with 1 million guests annually. The track is nicknamed "The Brickyard", and the venue self-describes as the "Racing Capital of the World". The garage area is known as Gasoline Alley, though Indy 500 racecars have used methanol and currently ethanol.
The Speedway is owned by Penske Entertainment group which is 67% controlled by Roger Penske's company Penske Corporation, with Fox Corporation owing a 33% stake in the company since July 2025, following its 2019 purchase of Hulman & Company and its assets, which included the Speedway, the IndyCar Series, and associated enterprises. Carl G. Fisher, along with investors James A. Allison, Arthur C. Newby, and Frank H. Wheeler comprised the founding ownership group. World War I flying ace Eddie Rickenbacker was the track's second owner (1927–1945), and incidentally he also drove in the Indianapolis 500 four times. Tony Hulman purchased the track from Eddie Rickenbacker following World War II, and the Hulman/George family owned the track for three generations (1945–2019).
Indianapolis businessman Carl G. Fisher first envisioned building the speedway in 1905 after assisting friends racing in France and seeing that Europe held the upper hand in automobile design and craftsmanship. Fisher began thinking of a better means of testing cars before delivering them to consumers. At the time, racing was just getting started on horse tracks and public roads. Fisher noticed how dangerous and ill-suited the makeshift courses were for racing and testing. He also argued that spectators did not get their money's worth, as they were able to get only a brief glimpse of cars speeding down a linear road.
Fisher proposed building a circular track 3 to 5 miles (5 to 8 km) long with smooth 100–150-foot-wide (30–45 m) surfaces. Such a track would give manufacturers a chance to test cars at sustained speeds and give drivers a chance to learn their limits. Fisher predicted speeds could reach up to 120 mph (190 km/h) on a 5-mile (8 km) course. He visited the Brooklands circuit outside London in 1907, and after viewing the banked layout, it solidified his determination to build the speedway. With dozens of car makers and suppliers in Indiana, Fisher proclaimed, "Indianapolis is going to be the world's greatest center of horseless carriage manufacturing; what could be more logical than building the world's greatest racetrack right here?"
Fisher began looking around the Indianapolis area for a site to build his track; he rejected two potential sites before finding level farmland, Pressley Farm, totaling 328 acres (133 ha) about 5 miles (8 km) outside Indianapolis. In December 1908, he convinced James A. Allison, Arthur C. Newby, and Frank H. Wheeler to join him in purchasing the property for $72,000. The group incorporated the Indianapolis Motor Speedway Company on March 20, 1909, with a capitalization of $250,000, with Fisher and James Allison in for $75,000 apiece and Frank Wheeler and Arthur Newby on board for $50,000 each.
Construction of the track started in March 1909. Fisher had to quickly downsize his planned 3 mi (5 km) oval with a 2 mi (3 km) road course to a 2.5-mile (4.0 km) oval to leave room for the grandstands. Reshaping of the land for the speedway took 500 laborers, 300 mules and a fleet of steam-powered machinery. The track surface consisted of graded and packed soil covered by 2 in (5 cm) of gravel, 2 in (5 cm) of limestone covered with taroid (a solution of tar and oil), 1–2 in (3–5 cm) of crushed stone chips that were also drenched with taroid, and a final topping of crushed stone. Workers also constructed dozens of buildings, several bridges, grandstands with 12,000 seats, and an 8 ft (2.4 m) perimeter fence. A white-with-green-trim paint scheme was used throughout the property.
The first event ever held at the speedway was a helium gas-filled balloon competition on Saturday, June 5, 1909, more than two months before the oval was completed. The event drew a reported 40,000 people. Nine balloons lifted off "racing" for trophies; a balloon by the name of Universal City won the race, landing 382 mi (615 km) away in Alabama after spending more than a day aloft. The first motorsport event at the track consisted of seven motorcycle races, sanctioned by the Federation of American Motorcyclists (FAM), on August 14, 1909. This was originally planned as a two-day, 15-race program, but ended before the first day was completed due to concerns over suitability of the track surface for motorcycle use. These early events were largely planned by one of the top names in early auto racing promotion, Ernest Moross, who earned fame for his bold and sometimes outlandish barnstorming events at fairgrounds tracks with racing star Barney Oldfield.
On August 19, 1909, fifteen carmakers' teams arrived at the track for practice. The track surface again became a concern with drivers being covered in dirt, oil, and tar and with ruts and chuckholes beginning to form in the turns. Speedway workers oiled and rolled the track prior to the gates opening to the public. Fifteen to twenty thousand spectators showed up, paying at the most $1 for a ticket. Louis Schwitzer won the first race held, a 5-mile, two lap event. Halfway through the first 250 mi (400 km) event, race leader Louis Chevrolet was temporarily blinded when a stone smashed his goggles. William Bourque, driving in a Knox, suffered a suspected rear-axle failure resulting in his car flipping end over end on the front stretch before crashing into a fence post. Both he and his mechanic, Harry Halcomb, died at the scene.