How the ancient and modern routes of transportation helped in the growth of India economy?

I assume you got this question from someone who didn't know what 'economy' means.

Greek oikonomia is a household. The English word means management, as in the class "Home Economy". Since management always involves pinching pennies, the word comes to mean frugality, and by extension, money management of all sorts. Did you buy something recently? Let's say you bought a pencil. What color? Did you look for a certain kind or grab one from the display nearest the checkout? All such choices in some area make up the economy of that area, usually measured in the local currency for convenience. That leads to some confusion because measuring things in paper money makes no distinction between a good choice and a bad choice. For example, does breaking a window enrich the economy by the cost of its replacement? This is not an idle question. A few years ago the US government offered money to people who destroyed their cars and bought new ones. Suddenly the prices for used car parts exploded. To make matters worse, most of the new cars came from outside the country, so the money did not all go to US auto makers. This sort of stupidity is common among politicians who are not aware of any distinction between economics and politics.

Now to your question. It should be obvious that you can not choose to buy from a dealer who can not deliver the goods. That concept is not considered a part of "economy", it is considered "trade". Trade routes are the first and most important concern when establishing trade. That is why cities are built on river banks instead of mountains.