The last few weeks have seen Portugal’s beast in the North rear its head again. Nazaré, named after the biblical land ‘Nazareth’, this wave frequently reaches heights of 50ft and higher. For context, this is a wall of water taller than a 4-story building. Nazaré’s story as a big wave motherland only begins in the 2000s, with Hawaiian Garrett McNamara and local Portuguese bodyboarder Dino Casmimiro.

Fast forward to now, and Tudor’s Nazare Big Wave Challenge is going off this week. So how do these mutant waves make their way to this sleepy Portuguese town?



The TUDOR Big Wave Challenge 23/24


On the North side of Nazaré lies a deep off-shore canyon, one of the largest underwater canyons in Europe. This gash in the seafloor lies scarily close to the beach at a depth of 20m. However, as you stray from the beach, it rapidly reaches 50m, before completely dropping off to a jaw-dropping 5km deep.

As swell funnels towards the canyon, it splits in two. One part travels through the canyon maintaining its power and gaining speed thanks to the incredible depths beneath it. The canyon also shifts the direction of the swell it holds, angling the waves face – on to the beach ahead.

Meanwhile, a resident current travels in the opposite direction from the beach towards this swell.

The other part travels alongside the canyon, just around the edge. These two parts meet again, and combine with the current to create the notorious ‘triangle wave’ Nazaré is infamous for. As they meet close to the shore, they collide, amplifying their size.



This underwater canyon will have points of sheer cliff edge, where the depth leaps from 50m to 5000m (Carapuço, M. M. et al. 2022).


This underwater wave generator also happens to regularly receive some of the strongest swells in the world, that travel uninterrupted across the Atlantic Ocean. Bring in a high swell period and a Northwest direction, you get magic.

Estimates say that this canyon amplifies the wave size at Nazaré by up to 3 times what it would be otherwise.


Check out a visualization of these mechanics by the World Surf League here.

Check out a visualization of these mechanics by the World Surf League here.


Nazaré’s truly unique underwater secret is responsible for generating the biggest surfable waves of all time, thanks to the refraction of the swell by the canyon and surrounding flats.


Refraction is the reason that other mutant waves exist. For example, the ‘entrance to Hell’ Skeleton Bay in Namibia, where lions roam the shore and 11 species of shark patrol the waves. As with Nazaré, it’s big risks for big wins. For example, Koa Smith’s 8-barrel dream wave back in 2018.

Another rogue giant occurs off the coast of San Diego, California. This is Cortes Bank, a hardly-submerged island 154km off the coast in the middle of the Pacific Ocean with a depth of just 6 to 12 ft.


Cortes Bank (Google Maps)

Cortes Bank (Google Maps)


Like sunlight through a magnifying glass, this underwater island sucks up swell and release waves of 80ft and higher. What makes Cortes Bank so fascinating is the mystery of what it produces. It feels like a sci-fi adventure, with rumors of 100ft waves, guarded by great whites, surfed on rogue missions reached by chopper ride. As more people brave the wave, we’re excited to see the true potential of this spot come to light.