Construction on new viewing stands for the Edinburgh Military Tattoo has revealed two structures dating to the late medieval period. The walls were believed to have formed part of the defense of the castle.
Archaeologists have opened two trenches at the site, which is beneath the castle's esplanade. The first revealed a wall forming the north perimeter boundary wall between the city and the castle. The second is believed to be part of a "defensive bastion which protected the entrance to the castle." Both structures date to at least the 16th century.
Excavations are scheduled to be closed to preserve the site.