The Denver City Cable Rail Way Building, Denver Colorado.
It's interesting to see how this sort of urban transportation has changed over the years. Many cities, such as Denver, had cable cars or horse drawn trollies (the two being quite different, of course). They later removed them. My uncle once told me me about riding on the back of trollies into downtown Denver, but when I was a kid, there was no transportation in Denver at all, or at least none that I can recall from when we'd visit the city for some reason. That is, no public transportation.
Downtown, however, by the 1970s Denver's RTD ran a bus line up and down 16th Street, which was otherwise closed to traffic. Within the last 20 years a light rail system has been put in, and the city is now putting in a rail system that will run out to Denver International Airport.
All these methods of transportation in Denver are similar in a way, of course. But notably dissimilar as well.
On another note, it's nice to see this interesting old building preserved and still in use, albeit for much different purposes, today.