[2] The hazardous nature of the rock prompted the Canadian government to remove the top of the mountain in a controlled explosion on 5 April 1958.

Ripple Rock was so named in 1862 by Captain Richards, RN,[5] because its summits were about at sea level and made a prominent standing wave in the fast tidal current of the strait.

[6][7] The first known large ship to fall prey to Ripple Rock was the sidewheel steamer Saranac in 1875, as it was heading north to Alaska.

In the 1860s a plan was started to link Vancouver Island to the mainland at Bute Inlet, using Ripple Rock as a mid-support for the bridge.

[dubious – discuss] In 1953, the National Research Council of Canada commissioned a feasibility study on the idea of planting a large explosive charge underneath the peaks by drilling vertical and horizontal shafts from Maude Island in the sound.

Stewart Limited and Boyles Brothers Drilling Company, were granted the contract, which cost in excess of 3 million Canadian dollars (equivalent to $28,585,714 CAD in 2018).

635,000 metric tons of rock and water were displaced by the explosion, spewing debris at least 300 metres in the air which fell on land on either side of the narrows.