National Highway 6 & Economic Corridor 1 (EC1) (commonly referred to as NH6), was a National Highway in India that has been separately designated under the new national highway numbering system. It was officially listed as running over 1,949 km (1,211 mi)from Surat to Kolkata. The route was also known as Asian Highway 46 (AH46) & Mumbai - Kolkata Highway and Great Eastern Highway.