Five decades ago, a local campaign to save a Tasmanian lake set in motion an international movement.
The world's first Green political party - the United Tasmania Group - was formed at the Hobart Town Hall on March 23, 1971, as locals rallied to save Lake Pedder in the state's south-west.
Australian Greens members are returning to Hobart on Saturday to honour that special day, 50 years on.
"It began when a bunch of everyday, caring people went into politics to protect our wilderness and stop the flooding of Lake Pedder," Greens leader Adam Bandt said.
"Now, we're an international political force that is at the forefront of climate action and social reform."
Hobart residents Patsy and Richard Jones helped form the UTG after the unsuccessful campaign to stop the flooding of Lake Pedder.
The party stood candidates in all five electorates for the April 1972 state poll.
They gained four per cent of the vote, which was not enough for a seat, but their actions sparked a national - and international - movement.
The Australian Greens now hold seats in the country's federal and state parliaments, while there are more than 100 Greens parties worldwide.
Mr Bandt said with a federal election eminent, the Greens' values of climate action and social reform were more important than ever.
"This election is going to be closer than you think," he said.
"It's going to be a choice between candidates that continue the old way of tearing up our forests and killing our planet, and the Greens, who will protect our natural world.
"With 50 years of incredible wins behind us and a clear plan for our future, the Greens won't compromise on our values."
