I remember two layouts from some 1990s MR issues and I am trying to find some info on the,
1.) First one appeared in either the 1999 or 2000 Edition of Great Model Railroads. It was a BN/BNSF/MRL themed layout that was able to host 100+ car trains with ease. And I think it was HO Scale.
2.) This one's a little harder. I think it was in a 1995-1998 issue of MR, It was a Canadian Railroad that had pretty high scenery. It may have been Jim Richards Athabasca Railway, but I am not sure.
Tom Danneman has a MRL in N-scale, and Bruce Rodgers in HO. I don't think either of those are a large as the one you are looking for.
Tom Cox's CN Prairie Region, in May 1997 issue?
What does "high scenery" mean?
DavidH661.) First one appeared in either the 1999 or 2000 Edition of Great Model Railroads. It was a BN/BNSF/MRL themed layout that was able to host 100+ car trains with ease. And I think it was HO Scale.
Bitterroute Lines, owner Kirk Thompson. HO scale 22'x26' - Great Model Railroads '99 page 74
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
"What does "high scenery" mean?"
Floor to ceiling scenery........
MR has, or used to have, the yearly indexes on this website that you could view and print out. I see from my collection that I have missed a few years now that they are no longer part of the printed magazine. But in some instances the paper indexes can be useful in ways the online index is harder to adapt to
The heading Layout description is what you want.
Looking at 1997, there was the Dolly Varden Mines HOn 2 1/2 layout in March page 116 that certainly has pretty, and pretty high, scenery in a British Columbian locale. The same author had an article in November page 118 about his HOn3 Port Caribou RR & Western Navigation layout - and again the scenery is high and pretty.
October 1998 had the Athabasca System (Clayton Barry, NOT Jim Richards') in N on page 70. A remarkable painted backdrop.
That gives an idea of what the yearly index can find.
Dave Nelson