A cart.
it called a cart or wheelbarrel
A cart.
carvan
It is not wagon trains. Groups of covered wagons are called prairie schooners. But we can also call it wagon trains, I guess.
You would hitch a horse to a wagon.
cause they are wagon burners xD
A horse drawn wagon on rails is called a sled or sleigh.
Doodle is pulled along in what is called a go cart in the story, but is probably something like a small wagon.
Wagon trains.
A young wagon is typically referred to as a "cart" or a "scooter."
A maker of wagons is called a wainwright.