Highway 85, running from the Haradh area near Saudi Arabia's eastern border to Badha, near their border with the United Arab Emirate is the longest, completely straight road in the world. It is about 160 miles (260 km) of road without any turns, bends or curves and runs through the ever shifting sands of the Rub al Khali, also known as the Empty Quarter. This is one of the hottest, driest places on earth, with temperatures reaching over 122 degrees (50 C) in the day and plunging to near freezing at night.

Other long, very straight roads include the "90 mile straight" in Australia, running between Balladonia and Caiguna and is actually 91 miles long. A 31 mile stretch of Highway 43, running between Beaver Creek and Gackle, North Dakota is the longest straight section of highway in the US.

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