The world's largest non-nuclear peacetime explosion

In 1958, an undersea mountain known as Ripple Rock was finally blasted into submission. The twin peaks of "Old Rip" lay north of Campbell River in the Seymour Channel, between Vancouver and Quadra Islands. At low tide, it almost tickled the water's surface, creating dangerous waves and whirlpools. Captain George Vancouver called it, "One of the vilest stretches of water in the world".

Between 1875 and 1958, 119 vessels were damaged or destroyed by Ripple Rock. For over half a century, people lobbied to get rid of it. They tried drilling it away - twice. The first time, the current snapped the cable on the drill barge. The second time, nine workers drowned when their boat capsized. The only solution, blow it up.

After 27 months of tunnelling from nearby Maude Island, the National Research Council had packed enough explosives inside the mountain to blow off the top. On April 5, 1958, at 9:31 a.m. - in one of CBC Televisions first national live broadcasts - Ripple Rock became Ripple Rubble.

The highest peak now reaches 14 metres below low tide, instead of three and the Ripple Rock explosion is still considered a magnificent feat of engineering.