Circuit of the Americas is a 3.427-mile (5.515 km) motor racing circuit near Austin, Texas. It is due to hold the Formula One United States Grand Prix on November 18, 2012, the penultimate round of the 2012 season. The circuit will also host the Texas Motorcycle Grand Prix, a round of the Road Racing World Championship — commonly known as MotoGP — in addition to the Australian V8 Supercars series, the FIA World Endurance Championship, the American Le Mans Series, and the Rolex Sports Car Series, all of which will make their debuts at the circuit in 2013. The circuit and Grand Prix were first proposed in the middle of 2010. The circuit will be the first in the United States to be purpose-built for Formula One. The layout was conceived by promoter Tavo Hellmund and 1993 Motorcycle World Champion Kevin Schwantz with the assistance of German architect and circuit designer Hermann Tilke, who has also designed the Sepang, Shanghai, Yas Marina, Istanbul, Bahrain, Yeongam, and Buddh circuits, as well as the reprofiling of the Hockenheimring and Fuji Speedway. The observation structure, amphitheater, grand plaza, and main grandstands were designed by architectural firm Miró Rivera Architects. In a news conference on July 27, 2010, Tavo Hellmund announced plans to build the track on about 890 acres (3.6 km2) of undeveloped land in southeastern Travis County. The majority of the site was previously planned for a residential subdivision called "Wandering Creek". In the same news conference, Hellmund also revealed that Texas billionaire Red McCombs was the project's largest investor. McCombs wished to call the site "Speed City", but the owners originally anticipated selling the naming rights to various parts of the facility for $7 million. On April 12, 2011, the track's name was announced as "Circuit of the Americas" at a press conference. The circuit homologation design was submitted to the FIA in Geneva for approval on December 17, 2010. HKS, Inc. and Tilke Engineers & Architects designed the track and Austin Commercial, a subsidiary of Austin Industries, was the general contractor. Construction began on December 31, 2010, and was due to be complete by June 2012. Following a stop-work order in December 2011, the completion date was revised to August. The first tasks were building the silt fences, taking core samples, and shredding existing vegetation. On January 21, 2011, a $900,000 check was posted with Travis County that permitted grading to begin. The money was to be used to restore the land if FEMA declined to allow the project to move forward because part of the site lies in a floodplain. FEMA issued a letter on June 28, 2011, stating the project meets its floodplain management criteria. In January 2012, Travis County announced that Elroy Road—one of the two primary public access roads to the circuit—would receive an upgrade to handle the volume of incoming traffic, but not before the running of the 2012 race. At the time of the announcement, the unstable clay soils under the road surface had caused Elroy Road to gradually buckle and shift, necessitating the upgrade. On June 13, 2012, Charlie Whiting—the FIA-appointed Race Director for Formula One—declared himself satisfied with the circuit's construction, scheduling a final pre-race inspection of the circuit for September 25, sixty days before the first race, which the circuit later passed. The first layer of asphalt was completed on August 3, 2012. Construction began laying the final layer of asphalt on August 14, and was finished on September 21. The track was officially opened on October 21, with Mario Andretti running the ceremonial first laps in a Lotus 79, the car he drove when he became the last American to win the World Drivers' Championship in 1978.