Actually, my last project was a "goat castle" - this week I put up 50 feet of board & batten walls on an addition to the barn, built a new hay feeder, and put in 50 or so feet of chain link fence with a bottom rail (as well as top rail.) Plus, spread 12,000 pounds of sand in their new home (for 5 male goats.) And, built a new pile of logs for them to walk/climb on.
I'd never do something as tall as the castle thing in the OP though - they're fainting goats. Getting startled up toward the top would mean toppling over to the ground below.
But, they're treated like kings - automatic waterers, free-choice hay 24/7, mineral blocks, protein blocks, and plenty of excellent grains.