There are also the ports in Saint John, New Brunswick, and, yes, Quebec City.
It goes without saying that a lot of those goods are transported by truck, so highway infrastructure is very important. For Newfoundland and Labrador, ferries are obviously very important. There has to be a ferry system to support trade. When the cost of crossing the Confederation Bridge between my province and Prince Edward Island dropped from $50 to $20, that directly benefited the people of Prince Edward Island and the people of other provinces who wanted to exchange goods.
Regarding rail, I'm not an expert, so I don't know all the details. However, I've attended a lot of meetings during which the major rail companies talked to us about their intermodal stations.
Some areas have huge ports. In Winnipeg, my colleagues are talking about an inland port. At the end of the day, logistical infrastructure is what makes trucking or rail efficient and prevents delays. For example, a rail car might be idle for two weeks, or it could be idle for only two days.
It's kind of the same thing as for international trade, but it's for local trade and internal trade.