KnowraCustoms unionLinked fromLinked fromThe 12 pages that link to Customs union, each with the reason it gives.All 12Broader topic 4Related 3Narrower topic 3Compared with 2European integrationRelated: The EU customs union supports integration by combining internal free trade with a shared trade border.Treaty of RomeRelated: The treaty set the EEC on a timetable toward this shared external and internal trade regime.Friedrich ListRelated: List supported the Zollverein as a way to create a larger market for German industry.