"It was an opportunity to thank the firefighters both here and from overseas, and also the community not just here in NSW but also around the world, who've shown their support." The ad rotates between two screens, starting with a message saying, "Thank you to the brave Australian and US firefighters defending Australia. And to the world for all your support." This gives way to a wall of flames, accompanied by the line: "Imagine fighting a bush fire higher than this billboard." Loading Replay Replay video Play video Play video The top of the billboard is more than 20 metres high.

Wunderman Thompson's national chief creative officer Simon Langley said that after a chat with the RFS, both agreed on a bespoke approach. "It was quite daunting to get an idea that was worthy of the site - but we thought just keeping it really simple and powerful, but also to say thank you, was the best way to go," he said. Mr Langley said after the RFS told them of the "amazing" donation, the creative team quickly came together, pro bono, to form ideas on how to use the scale of this billboard, and the best way to say thank you. "We just wanted to give people in Times Square an experience of how big these fires are and how brave these firefighters are," he said. "We thought this was a good use of the sheer scale of this billboard."

Despite the worst of the fire season now over, there are still 24 fires burning around the state, with 18 yet to be contained. Mr Allan said that, thankfully, heavy lightning strikes overnight had not had an adverse effect on fire grounds nor created new fires. About 350 RFS volunteers remain in the field on Wednesday, with many assisting the State Emergency Service with storm-related hazards. 'It's a message that resonates'

The Foundation and Friends of the Botanic Gardens, a charity which supports the preservation of plants and habitat, as well as funding plant science and climate-change solutions, will also be in the rotation at the same spot. CEO Melissa Ellis said the campaign would help raise awareness of the charity’s work. "It’s a message that resonates with everyone who cares about the planet." "All donations will support Australia’s eminent plant scientists and horticulturists at Sydney’s Botanic Gardens as they work on plant and habitat conservation, water sustainability solutions and fire recovery efforts at the Blue Mountains Botanic Garden," she said. Their ad shows a koala, along with the message "Help Australia. Our Plants. Our Future."

Loading The word 'future' rotates with the words 'life' and 'home', with the rest of the billboard staying the same. "It’s a message that resonates with everyone who cares about the planet and one that deserves to be broadcast from one of the world’s biggest advertising stages." The Blue Mountains were one of the areas hardest-hit by bushfires, and are only now rebuilding and re-populating habitats. "We are so grateful to the New-York media company Silvercast that was able to give us this extraordinary opportunity and we hope New Yorkers and visitors to the city will support our fundraising," Ms Ellis said.

Simon Moore, the creative director of Elton Ward Creative, who helped curate the campaign for the Gardens, said they only found out about the billboard spot last Friday afternoon. "With these last-minute jobs, you don't have much time to sit back and think about it. We had to pull out all the stops," he said. "It was like 'oh my god' – we're a fairly boutique Sydney agency, so doing something in one of the most famous places in the world was an extraordinary opportunity." Mr Moore said it was a "natural extension" of their existing campaign running in Australia, but also something that had to stand out as uniquely Australian in the sensory overload that is Times Square. "We had to connect the plants with something that people were familiar with that immediately said Australia," he said of the choice to use a koala.