The construction of the 9.2-kilometre-long Atal Tunnel connecting Manali with Leh, the world's longest highway tunnel above 10,000 feet, has been completed after 10 years. "The estimated period for completion was less than six years but it was completed in 10 years," chief engineer KP Purushothaman said. The tunnel will reduce the distance between Manali and Leh by 46 kilometres.