Police are trying to piece together the final movements of Simon Walker, 24, and Sherei Anderson, 32, found at a high point on the rocks at Kearneys Falls late on Monday.
They believe the couple had been trying to climb the steep and slippery rock above the swimming hole where they were spotted by a search crew in a helicopter.
Cairns Police Detective Acting Inspector Ed Kinbacher said the couple seemingly fell to their deaths after going for an early-morning swim.
Their clothing and shoes were found nearby.
“We believe this incident is a direct consequence of misadventure rather than any third party involvement,” he said.
The area where they were found is off limits to people.
Mr Walker was a member of the defence force in Townsville, and Ms Anderson the oldest in her family.
“As many of you may know, the person who raised me, my sister and my best friend passed away suddenly,” her sister Chloe wrote on Facebook.
“Thank you everyone for your messages and thoughts to me and my family, it certainly hasn’t gone unnoticed in the past 24 hours.”
Mr Walker’s mother, Beryl, shared an image of her son yesterday captioned “My Heart”.
One woman replied on Facebook: “My heart is absolutely shattered for you, Beryl, and all who love your beautiful Simon. God speed in getting to him. Take very good care of your fragile heart and please let all who love you help you through this.”
Friends, co-workers and former classmates have made tributes online.
“I’m so sorry, she was a beautiful person and a fantastic nurse who was very much loved by her colleagues,” Gaby Norman wrote.
“Love and condolences to you and your family at this time.”
Samantha Ann wrote: “Words cannot express the amount of love I have for this amazing, strong, outstanding human (Sherei).”
She said Ms Anderson was her best friend, her daughter’s godmother and was “meant to be” her birth partner for her current pregnancy.
“Sherei, I’m so happy that you left this world doing your absolutely favourite thing. I will forever miss you and I will forever have a hole in my heart. I love you,” she said in the post.
In another post, Cheryl Lyn Delaney wrote: “Chloe, you and your sisters have my deepest sympathies, Sherei was one of the most beautiful people I have ever met, she will be missed.”
“I went to school with Sherei, just want to send you and your family love. She was a wonderful person,” Sarah Leigh Harding wrote.
Police don’t yet know when the couple died.
They are calling for anyone who may have seen the couple at the campground to come forward to help them work out when they arrived.
The couple were travelling in a white ute and parked near the entry to Kearneys Falls path.
Officers know they were in Cairns on Thursday, because the man picked his partner up from the airport when she returned from a holiday in Japan.
In early September, Mr Walker posted on Facebook that they had visited Broadwater and Blencoe Falls in the Girringun National Park.
“Sherei got a bit scared because there were possible crocodiles in the water,” he wrote.
The previous month, they visited Alligators Nest swimming hole and Josephine Falls inland from Mission Beach.
“Mint day swimming and exploring, keen for more!” Mr Walker said in a post in July.
The couple were this time planning to camp for a few days before returning to Townsville. The Kearneys Falls walking track and viewing platform are temporarily closed for maintenance work.