Meandering peacefully across New Brunswick, the Petitcodiac River is, for the most part, a totally normal river. But twice a day, in the area around Greater Moncton, things get weird.

Tidal bores are a relatively rare phenomenon, even though when they happen, they happen with considerable regularity. The largest in the world is China’s so-called Silver Dragon, which manifests as a long-breaking wave 30 feet in height. But everywhere such bores occur, the basic mechanism is the same. On the Petitcodiac, the considerable tidal range and high waters of the Bay of Fundy force the river’s water to roll back in on itself, becoming a 1-to-24 inch wave that — improbably — travels against the current. As if a backwards river wasn’t a surreal enough sight, the single wave is often accompanied by its fan club - enterprising surfers looking for a different kind of ride.

The Moncton bore used to be much more pronounced, easily reaching heights of one to two meters. Unfortunately, a causeway constructed in 1968 considerably eased the wave’s speed and volume. Since the causeway’s removal in 2010, the wave is slowly, but steadily returning to its former self. Renewed and still rolling along, the Moncton tidal bore is a perfect example of how something that happens every day can still be completely remarkable.