There is no shortage of good waves in Portugal. It was just the other day we saw World Champion Italo Ferreira enjoying epic Supertubos, and then heading to Nazare for a tow session.

But that's not Dylan Graves' jam right now. Recently it was glacier surfing, Lagos wedges and now in the latest installment of the Vans' series Weird Waves, Graves and a crew of surfers from Barreiro focus their attention on riding the peeling lefts generated by ferries heading to and from Lisbon.

And, it looks like a whole lot of fun.

So, what does it take for a successful ferry surfing session to come together?

Well, here's one unique surf-quality factor: The more people crammed on to those ferries for their commute to work, the better your session is going to be.

The locals also have a trick up their sleeve in case it's a holiday and there are not enough workers to weigh the boats down - waving their boards to signal the captain, in the hope they take pity and punch the gas to crank things up a notch.

"It's just weird. You never know what you're going to get. The further the boat, the faster they go, the closer they angle in towards us ... the bigger the wave," says Nic von Rupp who enjoyed a session with the crew.

As Dylan sums up, the four ingredients to get this wave working are boat speed, weight, proximity and the tide. So, would you check it out next time you are in Portugal?

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