Prime Minister Narendra Modi will inaugurate Pakyong Airport, Sikkim's first-ever airport, later in the day.
The airport, which is located at Pakyong, is a Greenfield airport which will circumvent the need for a five-hour journey through mountainous roads and bring citizens of Sikkim closer to the state capital.
Located around 60 kms from the Indo-China border, the airport is strategically relevant from a security point of view. The Indian Air Force (IAF) will also find this airport convenient for landing and taking off, Union Minister for Development of Northeastern Region (DoNER), Dr Jitendra Singh, said on Sunday.
Sikkim's dream of having an airport will come true nine years after a foundation stone of the greenfield airport was laid, around 33 km from Gangtok, in 2009.
The airport is spread over 201 acres and is located on top of a hill about two km above Pakyong village at 4,500 feet above sea level, Sikkim Chief Secretary A K Srivastava said.
The airport was constructed by the Airports Authority of India and at present, the nearest airport from Sikkim is located 124 km away in Bagdogra in West Bengal, he told PTI.
The airport was constructed at an estimated cost of Rs 6.05 billion and is an "engineering marvel" for its soil reinforcement and slope stabilisation techniques keeping in view the altitude it was built at, Srivastava said.
Integrated structures comprising an ATC tower-cum-fire station, two sophisticated CFT, one terminal building for passengers, high-intensity runway lights, parking for over 50 vehicles are some of the features of the airport, the chief secretary said.
The reinforcement wall of the project is 80-metre-high, one of the tallest in the world, Srivastava said.
The Pakyong airport is located around 60 km from the Indo-China border.
The Indian Air Force (IAF) would be able to land various types of aircraft on the airport's runway with the construction of another 75-metre stretch adjacent to the main runway in the coming days, the chief secretary said.
The airport has a 1.75 km runway with a width of 30 metre. It has a 116-metre-long taxiway connecting it to an apron measuring 106 metre by 76 metre that can simultaneously accommodate two ATR-72 aircraft.
The airport has 3,000 sq metre terminal building and has a capacity to handle 50 in-bound and as many out-bound passengers.
Pakyong Airport Director R Manjunatha said the land for the airport was carved from the mountain side using massive geo technical 'cut and fill' engineering works.
The first commercial flight from Pakyong would begin from October 4, he said.
SpiceJet will operate 78-seater Bombardier Q400 flights to and fro Delhi, Kolkata and Guwahati everyday under the Civil Aviation Ministry's Ude Desh Ka Aam Nagrik (UDAN) scheme, Manjunatha said.
UDAN aims at enhancing regional connectivity.
Manjunatha said initially the airport would only cater to domestic flights, but later it will also provide international flight services connecting Sikkim with other countries like Paro in Bhutan, Kathmandu in Nepal and Dhaka in Bangladesh.
On March 5, IAF's Dornier-228 aircraft was tested from Pakyong, officials said.
SpiceJet followed it by conducting test runs of the 78-seater Bombardier Q400 from Kolkata to Pakyong on March 10. This led to security clearances for commercial operations, they said.
The Sikkim Police has been entrusted with the security of the Pakyong airport, the officials said.