EnterTRAINment Junction in West Chester, Ohio, USA, has the most impressive G-Scale layout I've ever seen. They were kind enough to allow me to shoot some spectacular video, including CAB RIDES, of several of their Main Lines, which cover three different eras: Steam, 1940's-50's, and Modern. You've got to see this to believe it! Here's the link:
https://www.youtube.com/watch?v=J-cN_e6XrCg&html5=1