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Question about Combination of “Traders & Barbarians" with "Seafarers” Barbarian Attack + Seafarers (in general) - Is a trade route interrupted if a settlement that represents the only connection between road and ship route is conquered?

Answer

The conquered settlement still exists. The trade route is interrupted, that is, only the road segments or the ships count toward the Longest Trade Route. However, the ship and the road segment adjacent to the settlement are not “open.”