Small escorted groups are to be allowed into David’s Tower, the castle’s first ever Tower House, which was built in the 1370s.
It is completely hidden from public view these days, situated behind the Half Moon Battery on the south-east corner of the castle.
The tower, built for the son of Robert the Bruce, was also used as a secret hiding place for Scotland’s crown jewels during the second world war.
Surviving parts of David’s Tower - which once stood 100 ft tall - were discovered exactly 100 years ago.
It had been built by King David 11 as part of a major reconstruction of the castle, however he never lived to see it completed.
The Tower played a significant part in Scotland’s history during the infamous ‘Black Dinner’ of 1440, during which the 16 year old Earl of Douglas and Wigtown and his younger brother were accused of treason (signified by them being served a black bull’s head on a platter) in the presence of the 10-year-old King James II. Rough justice followed immediately as they were dragged out into the palace yard and beheaded.
Remants of the tower were discovered in 1912 by a joint team from the Ministry of Works and the Royal Commission on the Ancient and Historical Monuments of Scotland.
Nick Finnigan, executive manager of Edinburgh Castle said: “David’s Tower is a fascinating part of Edinburgh Castle’s history. “It provided a secret hiding place for Scotland’s Crown Jewels during World War II due to fear of invasion and also witnessed the infamous Black Dinner of 1440.
“I am pleased to say that recent access improvements to David’s Tower have made it possible for us to consider taking small escorted groups to see the tower for themselves and learn about its intriguing past.”