https://en.wikipedia.org/wiki/Medieval_fortification http://en.wikipedia.org/wiki/Medieval_fortification http://en.wikipedia.org... Medieval history spiral stairs. Since Middle Ages Medieval fortification http://en.wikipedia.org/wiki/Medieval_fortification https://en.wikipedia.org/wiki/Medieval_fortification Medieval fortification English English fortifications of the Medieval era medieval fortification http://en.wikipedia.org/wiki/Medieval_fortification https://en.wikipedia.org/wiki/Medieval_fortification ARROW LOOPS en English en:Medieval fortification English