Grey's Anatomy is one of the longest-running television shows, that is now in its 17th season. Over the span of the show, Grey's has featured some amazing relationships and romances that are well talked about. But Grey's has also shown its viewers a wide range of friendships, some of which are as beloved as the relationships on the show.

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The friendships that are formed in the hospital have translated to friendships outside out of it, and viewers love the warmth that these friendships have. While some friendships are just plain fun, some have a mentor-mentee quality to them, which has allowed characters to grow and survive. Just take a look at these examples...

Cristina & Derek

Cristina and Derek fishing on Grey's Anatomy

Meredith was not really happy when this was happening. She felt like Derek was stealing her best friend. But Cristina was really going through a hard time after she was forced to operate on Derek under gunpoint.

Derek was not just grateful to Cristina for saving his life but he also knew that he would probably be able to help her better than anyone else because he too had gone through a phase where he had almost given up. For viewers, watching Derek and Cristina bonding on their fishing trip was one of the most interesting moments on the show.

Hunt & April

There were many times when April had messed up and had been forced to leave the program. But it was Hunt who brought her back, deciding that she deserved another chance. Hunt always had April's back and even when April was almost dying because of hypothermia, Hunt was the one who went and found her and led the efforts to bring her back to life. It was a very professional yet warm friendship they shared.

Jo & Warren

An image of Ben Warren in his fireman uniform in Grey's Anatomy

Fans would have loved to see more of this really funny and heartwarming friendship. After Stephanie left, Jo asked Warren to be her new Stephanie. Warren was the oldest one in their intern batch but generally got along with them really well.

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Stephanie and Jo were really close and would confide in each other when a problem arose. After Stephanie left, Jo and Ben sort of became confidantes and helped each other through their issues. It was a really fun dynamic between them.

George & Izzie

Geroge and Izzie smiling at each other in the hospital cafeteria in Grey's Anatomy

George and Izzie were extremely close right from the beginning. They were best friends and really cared about each other deeply. Even when they were going through a bit of a rough patch, they wanted the best for each other and went to great lengths to make the other person happy. O'Malley's death and Izzie's resuscitation was probably one of the most painful moments in the early Grey's Anatomy seasons.

April & Jackson

April and Jackson truly were better friends than they were a couple. They respected each other's beliefs and weren't forced to deal with them at a personal level, which was one of the foundational issues of their relationship.

They were really good friends, who loved hanging out with each other and constantly had one another's backs. They genuinely enjoyed each other's company.

Arizona & Richard

Arizona and Richard talking in Grey's Anatomy

A friendship that was incredibly adorable and cute was the one between Arizona Robbins and Richard Webber. They started hanging out a lot, going to clubs and trivia nights to blow off some steam. Richard even acted as a wingman for her.

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Their friendship was equal parts cute and equal parts hilarious. Unlike Richard's other friendships, this was based more on the personal than the professional and that's what set it apart.

Richard & Bailey

Bailey and Richard sitting on a bench together

Richard and Bailey are like work spouses. They knew each other so well that they could anticipate everything wrong with the other person. While it started out as Richard being Bailey's mentor, and Bailey being Richard's star student, they would become equals very quickly. Their friendship was based on mutual respect and affection, and they supported each other through the good times and the bad.

Mark & Callie

mark and callie laughing in Grey's Anatomy

An incredibly attractive couple, Mark and Callie were the best of friends. They stuck by each other and helped one another grow into more mature and responsible people. They even parented a child together.

Mark and Callie really loved each other, and their dynamic was really fun and exciting for viewers to watch as well. Mark's death was a huge blow to Callie who didn't just lose the father to her child, but also her closest friend.

Meredith & Cristina

Cristina and Meredith lying on a couch on Grey's Anatomy

The twisted sisters became friends from the get-go on the show. They developed a friendship that was unlike any other. They were each other's "person" and knew how to deal with each other so well. They were extremely competitive, moody, yet amazing surgeons, who always knew that they could count on one another for anything, at any time.

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Cristina's departure from Grey's brought a very sad end to this amazing friendship, but Grey's has found ways to keep her on the show still through phone calls and text messages.

Meredith & Alex

Meredith and Alex sat smiling together

Even before Cristina left, Meredith and Alex were very close. Meredith was probably Alex's only real close friend amongst the interns. And after Cristina left, they just became so much more attached to each other.

Alex and Meredith's friendship grew when they were adults with extremely important jobs and families and kids. They didn't have to deal with just petty drama from their intern years, but also real and heavy adult problems as well. They had stuck by each other until Alex packed up and left to be with Izzie. But until then, Alex and Meredith showcased the best that Grey's had to offer in terms of friendship on the show.

NEXT: Grey's Anatomy: 10 Ways That Meredith And Alex Were Friendship Goals