oval circuit. For instance, at Indianapolis the oval is run counter-clockwise, but the combined road course used during the IndyCar Series Grand Prix of Indianapolis is run clockwise. However the MotoGP races were run counter-clockwise, with some reconfigured corners to fix corner apex problems. Michigan was also an example of a clockwise combined road course. Another example is the Adelaide International Raceway in Australia which combines a 2.41 km (1.50 mi) road course with an 0.805 km (0.500 mi) speedway bowl. The Bowl forms a permanent part of the road course and also runs clockwise. At many tracks, multiple configurations are available for the combined road course layout(s). An example of an outfield combined road course can be seen at the Calder Park Raceway in Melbourne, Australia. The Calder Park complex has a 1.119 mi (1.801 km) high-banked oval speedway called the Thunderdome as well as a separate road course. The road course and the oval can be linked via two short roads that connect the front straight of the road course to the back straight of the oval. As they are separate tracks, this creates a unique situation where different races can actually be run on both the oval and the full road course at the same time. Also unique is that unlike most combined circuits which use the oval track's start/finish line and pits, in the case of Calder Park it is the road course start/finish line and pits that are used. This configuration was used only twice (both in 1987) and has not been used for major motor racing since hosting Round 9 of the 1987 World Touring Car Championship. Oval track construction booms in North America There have been two distinct oval race track construction "booms" in the United States. The first took place in the 1960s, and the second took place in the mid-to-late 1990s. The majority of tracks from the 1960s boom and the 1990s boom have survived, but some tracks failed to achieve long-term financial success. Incidentally, these two booms loosely coincided with the similar construction boom of the baseball/football cookie-cutter stadiums of the 1960s and 1970s, and the subsequent sport-specific stadium construction boom that began in the 1990s. Tracks built during the 1960s boom Daytona International Speedway (1959) Charlotte Motor Speedway (1960) Atlanta Motor Speedway (1960; substantially reconstructed in 1997; reprofiled in 2022) North Carolina Motor Speedway (1965; demoted to primarily a