The 34-year-old Spanish centre-back arrived at the Santiago Bernabeu in 2005 after they snapped him up from Sevilla for £18.5m.
And Ramos, who is currently club captain, has built a legendary reputation as one of the best defenders in world football and created an incredible legacy at Madrid already.
Alongside Casillas and Raul, the Spain captain admitted that Fabio Cannavaro was the third player that he "learned from every day."
Ramos told Spanish newspaper Marca: "When I arrived at Real Madrid I had to learn from veterans, like Raul and Iker [who, despite their youth, were already veterans].
"Cannavaro... another who I learned from every day. I will try to make the adaptation as good as possible."
Ramos, whose current deal with Madrid expires next summer, has made 650 appearances for Los Blancos during his remarkable 15 years at the club.
Raphael Varane has partnered alongside Ramos at Madrid and emerged as one of the favourites to succeed the Spanish World Cup winner as club captain.
However, the 27-year-old French World Cup winner insisted that Ramos remains an integral part of Madrid and branded him a "legend."
Varane told beIN SPORTS: "For the future, it's difficult to plan.
"Real Madrid is a very, very big club with great players. What is important is that everyone plays their part in the team.
"When we won our titles, our Champions Leagues, it was as a team, with eleven leaders on the pitch each time.
"Sergio is a legend in Madrid. The future for the moment I do not project about it, but for sure Ramos is a very important player for us.
"What is certain is that we are very complementary with Sergio Ramos, in our way of playing.
"We have qualities that complement each other perfectly. We have been playing together for several years, so we know each other very well.
"In defence, it works in pairs and this understanding is very important. For the future, after the departure of Ramos, it is difficult to project yourself.
"I am a leader in my own way. With my teammates, I talk a lot before matches about tactics and positioning. We each have our own way."
Featured Image Credit: PA
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