Circuit de Monaco downhill again to a double right-hander called "Portier," named after region of Monaco, before heading into the famous tunnel, a unique feature of a Formula One circuit. (Until 2009 only one other circuit, Detroit in 1982–88, featured a tunnel, but the F1 series now includes racing at the Yas Marina Circuit in Abu Dhabi, which presents a shorter tunnel at the exit of the pit lane.) As well as the change of light making visibility poor, a car can lose 20–30% of its downforce due to the unique aerodynamic properties of the tunnel. The tunnel also presents a unique problem
Circuit of the Americas to promote motorcycling racing, with Schwantz taking the role as official ambassador for COTA. In an episode of Speed TV's "Wind Tunnel" program broadcast on August 22, 2010, Tavo Hellmund revealed that the circuit would be 3.4 miles (5.5 km) long and would be made up of twenty turns with an elevation change of 133 feet (41 m). The final plan of the circuit was released on September 1, 2010, showing a design inspired by the European tradition of sculpting the circuit to the contours of the land. The design draws from several European Formula One circuits, including a recreation