Nazaré, Portugal has some of the largest waves in the world. During the winter time, swells from storms in the Atlantic march into the coast here and the unique structure of the sea bottom magnifies the swell into large waves. I spent 2 weeks in Nazaré hoping to film some of the big waves. I didn't get any of the 100ft monsters that hit the shore a couple times a year, but I did get waves consistently in the 30ft range and some over 40. I was worried that I would just miss some big ones as soon as I left, but fortunately it has been pretty calm with nothing huge in the forecast.