"Was supposed to be in Sydney for a few days to celebrate Lincoln's 30th birthday last weekend. Two changed flights later (and a twist of the arm from) @alyciajasmin) I ended up spending the entire week making up for some serious lost time," she wrote.
"My heart honestly hasn't felt this full in a year. So here's all my favourite moments."
Joining in on the nautical celebrations was Carrie Diaries star Alycia Debnam Carey, former Survivor player Sarah Tilleke, Fely Irvine from Hi-5 and Home and Away alums Tai Hara and Cassie Howarth.
Marny filmed herself playfully pushing Lincoln overboard into the water, while other celebs danced around to music and frolicked in the harbour.
The party was a belated celebration for Lincoln, who turned 30 on January 31.
Dozens of the actor's high-profile friends took to Instagram to wish him well on the milestone birthday.
"Haaapppyyyyy birthday bro! Hope you had an exquisite day! First pic needs to be on the wall! Amazing," former Home and Away star Todd Lasance commented underneath a throwback photo of Lincoln.
"This is everything. You’re a honey. Happy birthday Beautiful darling man xxx," Summer Bay alum Charlotte Best wrote, while Lynne McGranger commented: "Happy birthday lovely. Hope you’re celebrating in style 💙"
"Happy birthday handsome ❤️❤️❤️❤️," Georgie Parker, who plays Roo Stewart on the long-running soap, affectionately commented.
Lincoln played River Boy Casey Braxton on Home and Away from 2011 until 2014, saying his co-stars felt like "family".
"It was a chapter of my life that I will forever be grateful for," he said last year.
And his career has gone from strength to strength ever since leaving the Bay.
He was involved in a string of local productions including Doctor Doctor and Love Child before making the move overseas and nabbing roles in US productions such as Grand Hotel working with Eva Longoria.