Which is longest road or highway or motorway in the world
This article lists the world's longest road routes that are either officially numbered or otherwise known under a single name. Some of the roads may still be partially planned or under construction.

Pan-American Highway	30,000 km (19,000 mi)	Americas	Prudhoe Bay, Alaska, United States United States	Puerto Montt or Quellón, Chile Chile or Ushuaia, Argentina Argentina	Longest road according to the Guinness Book of Records.
Incomplete at the Darién Gap, causing the northern and southern segments to be actually long about 11,500 and 9,600 km.
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the longest road in the world is in Americas. The longest road is a highway called Pan American highway. It spans 30000 Kilometers or 19000 miles. It starts from Prudhoe Bay, Alaska in United states and ends at Puerto Montt or Quellón, Chile Chile or Ushuaia, Argentina Argentina

The pan american highway is registered as longest road in the world in guiness book of world records 

There are also other categories of longest road in the worlds like Asian highway which starts in Kapıkule, Turkey and ends in Tokyo, Japan. Asian highway is longest uninterrupted highway in the world. Length of the asian highway is 20557 Kilometers or 12774 miles

Longest road within the single country is in Australia. The name of the road is Highway 1. This is loop road and legnth of the highway is 14500 Kilometers or 9000 miles
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