Environmentalists, First Nations, and scientists arrived at the park in busloads to protest coal, oil and liquefied natural gas projects happening in B.C. and Washington State that they say are fuelling climate change.
"The Salish Sea is poised to become one of the largest exporters of fossil fuels in the world," said rally organizer Alexandra Woodsworth, with the Georgia Strait Alliance.
"We're here today to really call out that, to really shed a light on the combined impacts of all of these projects on the Salish Sea, and to come together and say we ... are not going to allow this part of the world to become a global carbon corridor."
The rally comes on the eve of what some are promising to be the largest climate action rally in history. It's called the the People's Climate March, and it is taking place tomorrow in New York and in cities around the world, including London, Paris, Rio and Vancouver.