Friends and families gathered in Nova Scotia Sunday to mark the third anniversary of the crash of Swissair Flight 111.

All 229 passengers and crew were killed when the jet crashed in the Atlantic Ocean, near Peggy's Cove.

The ceremony took place in the tiny community of Bayswater, and included a quiet, multi-faith prayer service to honour the victims.

Friends and family gathered at the oceanside memorial

One by one, people ran their fingers over the victims' names engraved on the memorial.

Afterwards, they were taken by boat to the actual crash site.

The annual memorial also reunites the victims' families with people in the local communities who got in their boats to help search for survivors after the crash.

The victims' names are engraved in stone

The flight was travelling from New York to Geneva, when pilots reported smoke in the cockpit. The aircraft crashed minutes later.

After three years, investigators still do not know what caused the fire.

Chief investigator Vic Gerden says he's frustrated that a cause hasn't been pinpointed.

"A specific spark – whatever the location – should not bring down an airplane with 229 people in it. There should be defences in place that prevent that," he says.

The Transportation Safety Board of Canada passed a series of recommendations based on what they've learned from the Swissair investigation.

While Safety Board head Benoit Bouchard says he hopes the measures will be passed by federal regulators, an official with the U.S. Federal Aviation Administration has suggested the recommendations may not be practical.