view of a bastion and a treadwheel crane at the guedelon castle in treigny, france. this site is actually under construction, as

building site architecture scaffolding round crane castle fortress mediaeval construction build france visit wall archaeology framework middleages tour tourism story heritage tower high engineering equipment visitors sky wood stone experiment learning yellow orange bastion tools balustrade treadwheel wooden human powered craftsmanship view guedelon treigny actually under experimental archeology project aimed recreating 13th-century