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
Baku City Circuit Baku City Circuit The Baku City Circuit () is a motor racing street circuit located in Baku, Azerbaijan constructed near Baku Boulevard. A lap of the circuit is , making it the second-longest circuit on the Formula One calendar. The inaugural Formula One race at the circuit was the 2016 European Grand Prix and its support events. A year later, in 2017, the circuit held the inaugural Azerbaijan Grand Prix. The event is organised by Baku City Circuit Operation Company (). In December 2013, Formula One President and CEO Bernie Ecclestone suggested that the race would be run in but