Fritz:
My immediate reaction to your question before reading the subsequent posts is that the site was Forks Creek, CO. Beyond the station should be the eating house, IIRC.
That "sign" that looks like an old fashioned clockwork key actually is a hand operated signal for trains to stop for orders and/or passengers. It's operated from inside the station by the station master or one of his employees. Can't tell from the photo but there probably is a similar signal blade mounted at the same level as what is seen but perpendicular to the blade that shows in the photo. The blade(s?) rotate 90 degrees. The heavy looking rod either is the rod that turns the signal or is a pipe containing such a rod. A set of 45 degree gears at the rod's outer end turned the signal; a similar set of 45 degree gears was mounted inside the station to bring the control rod down to the level of a man inside, possibly the telegraph operator.
Hart Corbett
Novato, CA