One of the longest traffic jams was 62 mi (100 km) long and lasted 12 days.

One of the longest traffic jams was 62 mi (100 km) long and lasted 12 days.

The longest traffic jam in the world was in the China National Highway 110, between Hebei and Inner Mongolia.

It lasted 12 days with a huge car panorama that stretched for more than 62 miles (100 km).

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