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
Bira Circuit Bira Circuit Bira Circuit is a motor racing track in Thailand, named after Thai formula 1 racing driver, Prince Birabongse Bhanutej Bhanubandh. The circuit has been operated by Bira Circuit One Company, Limited. The track, initially opened in 1985, covers an area of . It is a permanent motor and motorbike racing circuit with an offroad track, a rally stage and a go-kart facility. It is located in 111 Moo 5 Banglamung, Chonburi, Northeast of Pattaya. The circuit located on State Highway 36 which is from Bangkok and from the CBD of Pattaya. The circuit is twisty and bumpy and