Manager Roy Hodgson said Wilfried Zaha had been an iconic figure for Crystal Palace (AFP)
The 30-year-old forward joined Galatasaray on a free transfer after turning down a new contract with Palace and will receive a signing-on fee of 2.35 million euros ($2.6 million) and an annual salary of 4.35 million euros, the Turkish club said.
Zaha had been offered a reported £200,000 ($256,000) a week from the London club whom he joined aged 12.
He has scored 90 goals in 458 games for Palace and was sent on loan to the club twice during an unhappy two-year hiatus at Manchester United.
Parish called Zaha "our talisman, our greatest player" and said he "remains a true inspiration for all our young players in the academy".
"We would not be the club we are today without Wilfried," he added.
Palace manager Roy Hodgson -- who capped Zaha twice when he was England head coach before the player switched allegiance to the country of his birth -- said he would be a huge loss.
"I was really sad to hear that Wilf has decided to leave and start a new chapter in his footballing life," said Hodgson.
"The club is losing an iconic figure and although we regret that it has not been possible to persuade Wilfried to stay longer, we can only wish the very best of luck to him and his family."
Zaha's first spell with Palace drew the attention of Manchester United, who signed him for £10 million in 2013.
However, he never settled at Old Trafford, playing just twice, and aside from the two loan spells with Palace also went on loan to Cardiff.
He re-joined Palace permanently in 2015 but decided that despite being offered almost double what he will earn at Galatasaray it was time to cut the ties with the club.
"I want to thank Steve Parish, all of my team-mates, coaches and the entire Palace fanbase for always believing in me and encouraging me to get to where I am today," Zaha wrote before his move was announced.
"I have been blessed to play in front of you and call you family from the day you accepted me. From the bottom of my heart, I'm forever grateful."
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