Ripple Rock was an underwater, twin-peaked mountain in the Seymour Narrows of the Discovery Passage in British Columbia, Canada, a part of the marine trade route from Vancouver and coastal points north.
It was destroyed by a planned explosion on April 5, 1958. This is a National Historic Event in Canada. The Ripple Rock explosion was seen throughout Canada, live on CBC Television. It was one of the first live coast to coast television coverages of an event in Canada.
The explosion was noted as one of the largest non-nuclear planned explosions on record.