Originally Posted by CliffordK

Lots of yellow bulbs in use around here, which I believe are sodium lights???

As far as a couple of paths in Springfield, definitely not from the 1950's.

The Rosa Parks path was an old abandoned railroad through the 1980's, and I believe up until about 2000, when it was upgraded to a median strip bike path, maybe about the time the new hospital was built.

I haven't inspected the bulbs carefully, but they were short, upward facing, and white. And, working about 2 years ago, but mostly non-functional now.

The 42nd street path was an active railroad in the 1980's, usually with strings of rail cars loaded with logs on it. Also turned into a path around 2000. It got the lamp posts, but I never saw the lights on top of the posts.

Likely Springfield got some government grant money (State), and bought a bunch of pretty posts without thinking, just as municipalities started transitioning away from incandescent bulbs.