Seven Ghosts: the undular bore creates a river point break in the heart of Kampar River | Photo: Rip Curl

Tidal bores are mind-blowing natural events. They're relatively rare and only really shine to life in a handful of locations worldwide. The Seven Ghosts, also known as Bono, is one of those magical places.

In September 2010, four friends followed a hint and a super moon event and decided to check, at the last minute, an unknown daily river bore named Bono, deep in the Sumatran jungle.

Antony Colas and his brother Fabrice already knew similar phenomena.

They had ridden Le Mascquaret in France, Pororoca in Brazil, and the Severn Bore in England.

The siblings were accompanied by Patrick Audoy and Eduardo Bagé, who had surfed China's Qiantang River bore in 2007 before the Americans.

Maxence Peyras, from EyeSea Productions, shot the adventure.

When the team of five met the Indonesian tidal bore, they were mesmerized by what was happening in front of their eyes.

The Euro contingent was greeted by perfect-peeling two-to-eight-foot glassy waves for four days.

Seven Ghosts: perfect-peeling waves in the heart of Indonesia's Sumatra jungle | Photos: Antony Colas

A Secret Made Public

Antony Colas returned to the Seven Ghosts in December with more friends to experience the bigger daily Bono with eight-to-ten-foot wave faces on offer.

The adventure was broadcast on French mainstream television on January 28, 2011, for around 2.5 million viewers.

The unexpected surfing event triggered a broader attention.

In March 2011, Colas was appointed event manager of a new Rip Curl Search surf trip to the Seven Ghosts, which included Tom Curren, Bruno Santos, Dean Brady, Oney Anwar, and Tyler Larronde.

The project featured high-end logistics: three inflatable boats, two jet skis, and one helicopter.

In the end, the media professionals captured stunning pictures of the Indonesian tidal bore.

Among the photos and footage was the first-ever barrel ride caught on film.

The Rip Curl Search Seven Ghosts video was an instant success on YouTube, and a local industry flourished on the riverside.

Seven Ghosts: the Bono produces some fine chocolate-like barrels | Photo: Rip Curl

The Bono: A Unique Tidal Bore

The Bono, meaning "truth" in the local language, is a tidal bore similar to the one found in Pororoca, in Brazil's Amazon.

The phenomenon occurs in the Kampar River in the Sumatra province of Riau in Indonesia due to a unique combination of geographical, astronomical, and meteorological conditions.

As the river approaches the sea, its width increases, and it gains more water volume from tributaries.

During the rainy season, typically from November to December, this volume increase is more pronounced, and the estuary becomes even wider.

The tidal bore is created when high tide seawater flows upstream from the wide, shallow estuary into a rapidly narrowing river channel, clashing with the downstream flowing river water.

These waves can be quite impressive, traveling from the sea at speeds up to 40 kilometers per hour and reaching heights of four to six meters, often accompanied by a roaring sound and strong winds.

They can persist and travel for hours inland.

Notably, the Bono is not a single wave but a series of waves, sometimes appearing on both river banks or in the middle.

The Bono waves have also been attributed to a large number of shipwrecks in the Kampar River's estuary, with locals referring to them as "Seven Ghosts" and associating them with the people that lost their lives in here and the evil spirits associated with these tragic events.

When the Moon cycles and the tides align, you can witness the main wave breaking into several sections - the Seven Ghosts - and stacking just like in a point break.

This specific phenomenon is known as an undular bore - a leading wave followed by several "undulations" called whelps.

So, the Seven Ghosts is a section of the Kampar River where the bore slows down in a sandbar area and then multiplies once it gets back into deep water.

One Hour Long Rides

Despite the danger, the river is also used for boating agility tests.

River surfing is challenging due to the mud in the river and the presence of crocodiles and pythons near the shore.

Despite its medium tidal range (around four meters), the Seven Ghosts can produce ten-foot waves and barreling opportunities that can last for 10-15 minutes.

Nevertheless, for most of its course, you'll get gentle two-to-five-foot waves that intermediate surfers can easily ride.

The Bono travels up the Kampar River for four hours and up to 60 kilometers.

One of the largest ever recorded non-stop rides was locked in by Eduardo Bagé. The French-Brazilian surfer rode a wave for 62 minutes.

For the best and biggest waves, which can occur three or four times per year, you should wait for the biggest tides.

Get the right boat and support team to tow and rescue you if necessary.

Without it, you'll need to know where to prepare for the chocolate-like river swell near Teluk Meranti.

Hiring local crews to help you is a wise move. Experienced pilots will know where to drop you for the best surfing sections.

The Bono is easily accessible by land or sea via Pekanbaru (a short flight from Kuala Lumpur) or via Singapore, along one of Indonesia's last remaining peat swamp forests.


Words by Luís MP | Founder of SurferToday.com

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