When I was a kid I watched Death Valley Days on TV. It was sponsored by a cleaning product called Boraxo. The main ingredient of the soap is Borax, a mineral mined in Death Valley, hence the name of the show. The soap is now called
"20 Mule Team Borax."
The miners moved borax from the mine to the mill using a wagon train pulled by 20 mules. They needed all 20 mules to pull the two ore cars and a water wagon many miles across the rough and uneven ground of Death Valley.
If you saved the Boraxo box tops and sent them away with $.50 they returned to you a nice plastic kit of the 20 mule team (it is 1/67 scale) and ore cars.
Some of the early kits also included a covered wagon, several miners and a cowboy on a horse.
I assembled and painted the covered wagon first, posed it in front of a calendar photo of Monument Valley, and took one of my first table top model photos.
The plastic 20 mule team kit (minus the covered wagon) is still available through Mule Team kits for $24.95.