Spectacularly fast and hollow left-breaking rivermouth wave located near the fishing village of Mundaka in Spanish Basque Country; long regarded as Europe's premier surf spot; described in 2011 by three-time world champion Tom Curren as simply "the best wave in the world."

The exquisitely foiled sandbar that creates the wave at Mundaka is made by sediment washed down the Guernica River. September through December is the best time for surf here, as the sandbar is completely filled in, air and water temperatures are still relatively mild, the winds are frequently offshore, and the North Atlantic produces with some regularity storms of required size and duration to push waves into this corner of the coast. (Up-river dredging ruined the Mundaka sandbar in 2003, and the break lay dormant for nearly three years, before finally coming back into form in the Fall of 2006.)

Six to 10-foot surf at Mundaka is optimal; smaller waves are shorter and less hollow, while bigger surf will crumble and break before hitting the sandbar. Weeks can pass during the surf season where the waves don't get over four feet; when the surf is up, high tide will almost always kill the waves for four or five hours. "Think of Mundaka as if it were the best restaraunt in town, but you never know when it's going to be open," as Surfer noted in 2010.

When Mundaka is at its magical best—just a dozen times per year—surfers can fit as many as four separate tuberides into the same 300-yard-long wave. Later in the season, the air and water temperatures can be uncomfortably cold (into the mid-40s and mid-50s, respectively), and the sandbar is often thrown out of alignment, creating a less predictable wave. Wetsuits are required at Mundaka; a full wetsuit and booties are often used later in the year.

Exactly when Mundaka was first ridden, and by whom, is unknown, but it was a favorite among a small network of travelling surfers by the late '60s. Surfer magazine published a two-page overview photograph of Mundaka in 1973, showing ruler-edged waves peeling across the rivermouth, with a charming Old World hillside village in the background. Mundaka  became a must-ride break for any surfer traveling through Europe. "You can't really see the break until you're almost on top of it," California surf journalist Kevin Naughton wrote in 1993, describing the approaching drive. "But when you round the final bend, it's one of the greatest sights in a surfer's life."

Not surprisingly, the lineup at Mundaka has been crowded—often insufferably so—since the early '80s. A small number of regional, national, even international, surf contests were held at Mundaka in the 1980s; the 1999 Billabong Mundaka Pro, won by Australian Mark Occhilupo, put Mundaka on the world pro circuit for the first time; other winners included CJ Hobgood and Bobby Martinez.

Mundaka Surf Shop was opened in 1984 by expatriate Australian Craig Sage, and has long been the focus of the local surf community; the 1988-founded Mundaka Surf Club has an office in city hall, overlooking the break.

Mundaka has appeared in more than a dozen surf movies and videos, including Atlantic Crossing (1989), Lost . . . On the Road with Spike (1995), and Surf 365 (1999). British-published Surfer's Path magazine devoted its entire December 2000 issue to Mundaka.

Surfing magazine picked Mundaka as one of the "25 Best Waves in the World" in 1989, Australia's Surfing Life magazine in 1997 cited it as one of "Ten Waves Every Surfer Should Ride," and Surfer ranked the break #11 on their 2011 list of the "100 Best Waves in the World."