Castles became obsolete because of cannons.
Castles often lacked glass windows.
Castles could trap invaders between two gates.
Castle toilets sometimes emptied straight outside the walls.
Some castles stacked walls inside walls.
Many moats were dry.
Castles sometimes took decades to complete.
Famous spiral-stair myths may be just myths.
Castles could consume huge food stores without a single battle.
Boiling water was often cheaper than oil.
Castles could be defeated by poisoning their water supply.
The keep was a castle's last line of defense.
Castles were built for defense, not comfort.
Castles were originally built from wood, not stone.
Castles often contained entire villages behind their walls.
Castle arrow slits looked narrow but opened wide inside.
Castles could survive sieges for months.
Castles sometimes housed hundreds of people.
Castles were designed to survive sieges lasting months.
Murder holes attacked enemies from above.