“Lauren didn’t go to Paris. She's going to always be known as the girl who didn't go to Paris.”

It’s one of the most quoted moments from The Hills, and now ET has the full story behind the line.

Here’s the backstory for those who might need a refresher: At the end of the show’s first season, Lauren Conrad opted to stay in Los Angeles and spend the summer with her then-boyfriend, Jason Wahler, instead of taking a Teen Vogue internship in Paris. Her co-star, Whitney Port, wound up going on that trip.

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Port tells ET she’s not sure why cameras didn’t follow her overseas.

“The show was over at that point, and I think they had all the footage that they needed for the season,” Port says. “I think maybe they didn't want to invest in it or something.”

When the two stars returned to Teen Vogue’s L.A. offices at the end of the summer, editor Lisa Love remarked, “Lauren didn’t go to Paris. She's going to always be known as the girl who didn't go to Paris.” ET reached out to Love for comment on coining the iconic phrase, but got no response. (Conrad recently told InStyleshe believes it was actually Vogue’s Anna Wintour who first came up with the term, which Love later stole.)

“We had a big disagreement, [creator] Adam [DiVello] and I, over Lauren’s decision not to go to Paris,” executive producer Liz Gateley tells ET. “I said, this is the perfect ending, because every girl makes this decision. She thinks she’s in love, and she’s going to spend the rest of her life with this person, and that was the relatable choice, and Adam was so upset!”

“He really wanted to try to convince her to go, and she was adamant that she was not going to pursue an internship in Paris,” Gateley continues.

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“We tried to convince her, but at the end of the day, she wasn’t going,” Gateley recalls. “That was an authentic moment to that [theme of] coming of age. It’s like, who doesn’t look back and wish they had gone to Europe for the summer? Or taken that internship in D.C.? Or whatever it was, because they stayed behind for a boy or a girl. I mean, everybody does that. It was perfect.”

Of course, Conrad’s summer at the beach with Wahler did not go as planned.

“Honestly, that was when things started to get pretty rough,” Wahler recalls of wrapping season one. “We ended up breaking up … She did not go to Paris. That's not my fault though! That was her decision.”

We think it all worked out for Conrad in the end -- for more show secrets, check out our chat with Whitney Port below.