Does anyone remember a US layout being shown on PBS in the early 1990s?

[OnTheBranchline]

I remember as a child watching a taped video of some massive model railroad layout. It was made up of various sections (probably 6-7) with an narration of the layout/trains/era with interviews of the people who made the layouts. It would follow the route of a train and then switch to another train when it reached a different section of the layout.