Managing protection of trade routes:
Trade routes are defenseless. They don’t give visibility in the map, so if we are sending to a far country, we can’t see if there are enemies nearby or not, and they can be killed in a single turn. (Ending the trade route, and losing the trade unit).
When making trade routes in un-safe areas, you need to send some units as scouts/guards to protect trade route area. Especially in sea trade, we can send trade route to very long destinations, we need to protect our trade route. If we are losing trade routes, its a net loss. It is better to not have any risky trade route. But having empty trade route slots.
In the side image, I am guarding my trade route against barbarian ships. (They have destroyed two of my trade routes in that game). As you can see, I have build 3 great galleasses(venetian unique ship) and located them in locations, where I can see all trade route securely. If you get in war with country you are trading with, all trade routes are breaked, but trade units aren’t lost.
Note: Sea trade routes change route when Astronomy technology has been researched. They turn into the closest route possible (straight line maybe). (In the above picture you can see the trade route is wrapped around the coastline). When you have researched astronomy, make sure to relocate your guard ships to new location.
In the below picture, you can see my trade income as Venice (venice trade limit bonus)
As you can see, 100 out of 150 gold income is from the trade routes.
Every country has a trade limit. It begins with 2, and increases by +2 by technologies that states to increase this limit.
You can see this in the Picture below.
This limit shows you how many trade routes you can create. When limit is filled, you can’t create any additional trade routes.
In this guide, i have used pictures from a game I have played as Venice. And in Venice, this trade limit is double of the ordinary. (I recommend Venice to every reader, it’s a very different experience, it’s like playing as a city state. You can’t create settlers, and captured cities remain as puppet.)
Note: The city connection bonus remains same in brave new world. (the bonus when you link cities with road connection or harbor, you gain gold. This has nothing to do with trade routes.)