Goats are very strong, and of course sure-footed. One of the cool uses for goats around the world is as pack animals, and pulling carts. Here is a fun video of a pet goat pulling a boy in a homemade cart.
In the late 1800's it was very fashionable for children to have fancy carriages pulled by goats in Central Park in New York City. President Harrison even had a goat cart for his children on the White House lawn.
Training should start early, and it does take lots of time and work to get it right. Our baby Nubians, however, have conned us into letting them ride the cart. I think we'll have to start over with some baby Toggenburgs!