One Tree Hill knew a thing or two about building couples that fans would root for ionately. Even nearly 20 years after the series debuted, fans remain invested in the series' romantic relationships and still frequently debate which couples were the best and who should have ended up together.

Every core couple in the series has its merits, even though they don't all end up together. Some couples get the fairy tale happily-ever-after that fans want for their favored pairs while others are star-crossed. Yet every couple, no matter how their story ends, has one key romantic moment that fans come back to again and again.

Skills And Bevin: The Notebook

Bevin Mirskey and Skills Taylor cuddle on the couch in One Tree Hill

The relationship between Lucas's best friend, Skills Taylor, and the bubbly airhead cheerleader, Bevin Mirskey, was easily one of the biggest surprises during One Tree Hill's nine-season run. These two shouldn't have made any sense together, but their sweetness complemented each other well, quickly causing them to become one of the series' most beloved pairs.

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In the early days of their flirtation, Bevin selected Skills in the fantasy boy draft game. On their date, Bevin decided to "Notebook" him, which meant that they spent the night together watching the classic romantic drama The Notebook. Skills had a completely emotional response to the film, leading to the two cuddling together on the couch and quickly becoming inseparable.

Brooke And Lucas: "I Need You To Need Me Back."

Brooke Davis and Lucas Scott silently dance with each other in One Tree Hill

Brooke and Lucas's romance was one of the most popular storylines in the series, no matter how dramatic and ill-fated it may have been. The debate has continued as to whether Brooke or Peyton was really Lucas's true love, and even though Lucas ended up with Peyton after all, it was clear that he and Brooke shared a unique first love together that no one can overlook.

Ironically, their best scene came during the final dissolution of their relationship at the end of season three. Both Sophia Bush and Chad Michael Murray were at the top of their acting game when they emotionally fought about communication problems in their relationship, with Brooke tearfully proclaiming, "I am not pushing you away, Lucas. I am holding on for dear life, but I need you to need me back." Their mostly silent, pained dance together during Nathan and Haley's wedding reception after that was one of the entire season's most beautiful scenes.

Clay And Quinn: "Til Kingdom Come."

Clay Evans and Quinn James on the beach in their dream in One Tree Hill

Clay and Quinn were introduced in season seven of One Tree Hill as a way to replace Lucas and Peyton, both as individual characters and as an integral romantic relationship. The series somewhat rushed into their romance, however, which has made its popularity with fans less enthusiastic than some of the series' original core relationships.

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But in season eight, these two did share a romantic moment for the ages - even if only in their dreams. After they were both shot by Clay's stalker at the end of season seven, they found each other on a dreamy beach while unconscious and professed their love for one another - "til kingdom come."

Keith And Karen: "Look For Me In The Lilies."

Karen Roe dreams of kissing Keith Scott in One Tree Hill

One Tree Hill definitely had a real knack for incredibly romantic dream sequences, but none of them compare to the beautiful, heart-breaking moment that Keith and Karen shared in the season four finale. After Karen gave birth to their daughter Lily, she briefly reunited with the late Keith in her dreams, and even saw an older version of their daughter, too.

It was the emotional reunion fans longed for after Keith's senseless murder took the character away from One Tree Hill far too soon. It also promised an eventual reunion for these two star-crossed lovers, as Keith implored Karen to return to take care of their daughter by reminding her that he would be waiting for her, and she could "look for [him] in the lilies."

Brooke And Julian: "If You Say So. They End Up Together."

Julian Baker walks in on Brooke Davis dancing at Clothes Over Bros in One Tree Hill

Brooke Davis had many love interests across the first six seasons of One Tree Hill, but none of them were the right man for her until Julian Baker entered her life. When Julian first arrived on the scene, he was arrogant and abrasive, looking to win back his ex-girlfriend Peyton Sawyer by working on the adaptation of Lucas Scott's novel.

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But in coming to Tree Hill, he found Brooke instead, and realized she was everything he ever wanted. In their most memorable moment, Julian walked into the Clothes Over Bros to find Brooke dancing to "Don't You (Forget About Me)" by Simple Minds from The Breakfast Club. This resulted in the hilarious and all too accurate commentary that, in the world of The Breakfast Club, Brooke was "the priss" while Julian was "the stoner," characters who, as Julian points out, did in fact end up together.

Jake And Peyton: "I Could've Held You In My Arms Forever."

Jake Jagielski looks tearfully at Peyton Sawyer in One Tree Hill

Peyton may have ended up with Lucas after everything, but it's pretty hard to deny that Jake Jagielski was Peyton's best love interest on One Tree Hill. These two didn't have an easy time as a couple due to Jake navigating a fraught custody battle with his daughter Jenny's absentee mother. At the end of season two, Jake was forced to leave town to try and find his daughter after the mother abducted her.

Jake and Peyton exchange a tearful goodbye in her bedroom, with Jake begging Peyton not to let this loss weigh her down and move on with her life, no matter how much they love each other. Before Jake left, he delivered the entire show's most romantic line: "You know, I could've held you in my arms forever. Still wouldn't have been long enough."

Lucas And Peyton: "It's You."

Lucas Scott embraces Peyton Sawyer after the Ravens basketball game in One Tree Hill

It took three and a half seasons for Lucas and Peyton to find each other at the right place and the right time. Even though it wasn't smooth sailing for them after this moment, and while they would still break up for years afterward, the scene in season four in which they came together as a couple was one of the most exciting moments in the entire show.

On the heels of the Tree Hill Ravens' big tournament win, Lucas sought Peyton out on the basketball court and echoed words back to her that she had challenged him to figure out earlier in the season: "It's you. When all my dreams come true, the one I want next to me... it's you. It's you, Peyton." His declaration, followed by their emotional kiss as the confetti fell down around them, cemented this moment as the best in the Leyton history books.

Nathan And Haley: "Thank You For Being Worth It."

Haley James Scott hugs Nathan Scott in their kitchen in One Tree Hill

As its longest-running couple, Nathan and Haley are often considered couple goals on One Tree Hill. Even though they lasted all nine seasons, they had their fair share of ups and downs, most notably in seasons five and six following Nathan's career-pausing injury and the threats of Nanny Carrie trying to tear their marriage apart.

But at the end of season six, all of their dreams seemed like they were coming true when Nathan informed a tearful Haley that he had made it to the NBA at long last. "Thank you for believing in me," Nathan told her as he embraced her, to which Haley responded, "Thank you for being worth it," while pulling him into a kiss and leaping into his arms. If the series had ended there, it would have been a true fairy tale ending for these two.

NEXT: 10 Best ing Characters On One Tree Hill