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 The circuit was 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 circuit has FIA Grade 1 license. In a news conference on July 27, 2010, Tavo Hellmund announced plans to build the track on about of undeveloped land in southeastern Travis County. The