The two-lane Lærdal Tunnel was ceremoniously opened by King Harald on November 27, 2000, and opened to the public in 2001. This tunnel is an extension of I-90, and is located in Boston, Massachusetts. Delaware Aqueduct is the longest tunnel in the world at 85 miles long and 13.5 feet wide. Of its 31 miles, 23 miles are situated beneath the English Channel. (The world’s second longest, the St. Gottard Tunnel in Switzerland, is only 16.92 km, or 10 miles). The United States has some of the longest tunnels in the world. The Gotthard Base Tunnel started in 2004, and travels underneath the Swiss Alps for 35.4 miles. Although Lærdal Tunnel is currently the world's longest road tunnel, it's not the longest tunnel overall. This tunnel is an important part of the extension of a ferry-free road link while avoiding the destruction of the natural landscape. This enabled the crews to drill from four sites, which shortened the construction time. Ted Williams is one of the longest tunnels in the United States – at 1.6 miles. But the world's longest tunnels are definitely not the place for a car to break down. The tunnels serve different purposes in the states they are located. Also Read: Atal Rohtang Tunnel To Open For Traffic On October 3, 2020 The Atal Tunnel is 10.5-metre wide and offers traffic density of 3,000 cars and 1,500 trucks per day with a maximum speed of 80 kmph. It cost a reported $113.1 million to construct. The tunnel between Aurland and Lærdal on the main road between Bergen and Oslo, Norway, measures 24.5 km. Tunnels are some of the most amazing marvels of engineering. After finishing, it took the title of world’s longest road tunnel, previously owned by the Swiss Gotthard Road Tunnel. The great breakthrough in engineering and construction has ensured infrastructure today with a high level. Here are some of the longest tunnels in the US. Earlier this week, the new longest tunnel in the world was completed. This tunnel was opened in 1995, and is still open today. (15.2 miles) in length. This plant keeps the air quality inside the tunnel at very high standards, removing dust particles and nitrogen dioxide from the air. Lærdal tunnel was the first tunnel in the world to have an air treatment plant included in the design. Largest Tunnels in the US. The Laerdal Tunnel in West Norway is the world's longest road tunnel and cost $153 million to build, which works out at $6,250 per meter. The top six on the list are all water aqueducts (the longest being the 85-mile Delaware Aqueduct in New York State), while dozens of subway tunnels all around the world are longer than the Lærdal Tunnel. The Channel Tunnel, commonly referred to as the Chunnel, is the world’s longest undersea tunnel. An access tunnel of 2.1 km (1.3 miles) was built from a side valley, Tynjadalen (Tønjum Valley), 6 km (3.72 miles) from the Lærdal side. Here are the glimpses from the inauguration of #AtalTunnel, the longest highway tunnel in the world by PM @narendramodi today. How is the air quality inside the world's longest road tunnel?