How you could soon go from Mumbai to Pune in 48 mins, Delhi to Siliguri in 6 hrs

Suppose you had a choice. You live in Delhi, and plan to visit Siliguri, a city in Bengal, about 1,500 km away from the capital.
You could fly, or take a train. A flight would cost much more but you would reach in about five hours – say, a one-hour commute to the airport, two hours at the airport, dropping your bags, clearing security, reaching that far-away gate where your plane will take off from, and then a two-hour flight.