We don't often move our chicken tractors very far. We move them onto new grass 1-3 times a day, but we don't usually move them long distances. However, when we processed our last batch of chickens and decided to start moving our turkeys, we decided to put our tractor of laying chickens next to the turkeys.
The ending of the story was that we eventually got them to where we wanted them to go, but it was nearly a disaster, and we were all worried during the adventure that we were going to lose some chickens due to fatigue or death under the tractor.
We hit a patch of gravel. Since these chickens have only been on hay and grass, they did not know what to do with the gravel and refused to move forward. We could not get them to walk. So John opted to get into the tractor and scoot along with them while Jacob pulled the tractor. It was well over 90 degrees that day, and John actually got so hot, he nearly passed out after spending nearly a half hour crawling with the chickens to their new home.
But, it did work! We didn't lose a single chicken, and I managed to catch the whole thing on video:
These types of "adventures" are actually what cause farm life to be so challenging. You think you have a plan. You think the plan will take just a few minutes. And the animals (or weather or landscape or materials) decide something entirely different on your behalf, and you end up spending half a day doing what you thought would only take a portion of your morning.