Twice a day, the Shubenacadie River transforms from Sea of Tranquillity to Victoria Falls when 100 billion tons of seawater from the Bay of Fundy pushes 20 miles inland at 30 miles per hour. The Shubenacadie’s is not the world’s only tidal bore, but it’s the one place on earth where customers can pay an outfitter for an effort-free three-hour roller-coaster ride. “There’s times you go and it’s just a ripple,” our guide, Tyler, told me. “Then there’s extreme tide. You’ll want to be holding on to the ropes real tight.” Our group of six put the 16-foot Zodiac in the calm water just north of Fort Ellis, and Tyler beached us on a sandbar in the middle of the Yoo-hoo-colored river. Eagles soared overhead; a nearby mudflat beckoned. I took a few steps and was quickly mired waist-deep in quicksand. With the tidal maelstrom scheduled to arrive in minutes, I clawed at the muck—which resulted in further cementification. Soon Tyler came to free me, and just in time—five minutes later the water arrived in surges. Tyler torpedoed us bow-first into the torrents, and as we made laps over a bottlenecked stretch of the river where the swell was hitting 10 feet without pause, my fellow passengers shrieked with delight. One was tossed overboard. Before long the Zodiac resembled a surfaced submarine, and I was sucking water—my pants soaked, my toes pruned, and my Nikes left behind, deep in the quicksand.

GET THERE: Fly to Halifax and rent a car for the 30-minute drive to the Shubenacadie Tidal Bore Rafting Park in Urbania (cottages, US$130). The daily four-hour Zodiac trips are US$90.