The north entrance of a defensive tunnel for the original fortifications of Dockyard has been discovered by archaeologists.

They made their find while carrying out preparation work before volunteers arrive at the site as part of the XL Global Day of Giving.

Bermuda Maritime Museum director Ed Harris said the south entrance of the then-completely unknown feature had been found last year. It is 71 feet long and was mostly filled with rubble.

"Last Friday, we used an excavator to discover the northern doorway to the tunnel and were delighted to find that it was completely intact and made of hard Bermuda limestone in the Dockyard tradition," said Dr. Harris.

"This tunnel would have allowed soldiers to go from the Dockyard under the original defence ditch into counterscarp galleries from where they could fire on the enemy in the ditch.

"Until the discovery of this tunnel last year, historians only had a few hints from paintings that the original plan for the defence of the Dockyard was actually built, in part or in its entirety, since all traces of the original fortifications were removed when Casemate Barracks and its companion buildings to the south and north were built.

"The excavation of the tunnel this week will give us a more complete understanding of this remarkable piece of early fortification architecture in the Dockyard."