iron ranger n. an unattended container or automatic machine that receives visitor fees in a park, parking lot, or other public use facility. (source: Double-Tongued Dictionary)
Further reading
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In the 1920’s, Americans were warned of a new danger sweeping across the country. This menace that harmed people’s health, ruined minds, and threatened marriages. The culprit? The national obsession with a new form of entertainment: crossword...
We do have iron rangers, in the sense you define above, at some parks here in Minnesota but, I’ve never heard them called that. This may be because in MN “iron ranger” already has a decades old definition.
An iron ranger is a person from north central/northeastern MN – due west of Lake Superior. This area is known as the iron range because of the many iron mines.