Probably the Rio Grande.
My interest in railroads in general goes way back to my pre- kindergarten years. My father was fascinated by trains; and he encouraged my interest by occasionally taking me to see trains go by and to exhibitions of new railroad equipment and by buying magazines. Before I could read, he would read them to me.
The oldest Trains Magazine (other than back issues later purchased) is one from December, 1953 -- maybe a gift from a railfan Dad ran into while I was in kindergarten (1954-55). This issue is the one with the Fred Jukes photos taken around Chama.
At Travel Town in Griffith Park in Los Angeles was the Oahu railroad equipment. And at Knott's Berry Farm there was the Rio Grande equipment.
Then there was the Beebe books like
Narrow Gauge in the Rockies. That was a book that my mother checked out of the adult section of the public library so that I could read it at home. Later I got my own copy.
In September of 1959 the family took a late summer vacation trip to Lake Tahoe going through the Owens Valley. I had already had been gifted a copy of John Hungerford's little booklet "The Slim Princess, the story of the Southern Pacific Narrow Gauge." And my mother wrote to the agent at Owenyo to find out the operating schedule. But our travels missed seeing the actual operations.
A few summers later -- when I was a young teenager -- we made a automobile trip to see relatives in Nebraska going by way of Denver to see a cousin who just began his teaching career. My mother planned the trip making advance motel reservations to ensure that we kept on schedule. When she told me the route through Colorado I remarked that I could not have planned a better trip Overnight at Durango, but no extra day to ride the train. However, while my father and brother slept-in my mother took we down to see the train depart. Also at the depot I found copies of the early issues of Colorado RR Museum's annuals for sale and I bought these issues. We drove north to Montrose, then east for the next night at Salida. Then north to Leadville and then toward Denver. I was given several hours that afternoon to see the museum in Golden while the family did something else. The 346 was switching the cars around that day! That night's stay was someplace between in northeast Colorado on the way to Lincoln, Nebraska. Return to Pasadena was via Cody, Wyoming, and Yellowstone Park and Las Vegas, Nevada.
Brain Norden