The Keeping Up with the Kardashians series finale aired Thursday on E!

The Kardashian-Jenners are saying a bittersweet farewell to Keeping Up with the Kardashians

The family paid tribute to the show that made them famous on Thursday, the day of the iconic reality series' finale. Kourtney, Kim and Khloé Kardashian shared some thoughts on Twitter as the episode aired.

"What a magical past 15 years it's been! All of the friendships we made and things we've experienced! Wow blessed! #Blessed #KUWTK," Kim wrote in one tweet, later sharing a clip of fireworks from the finale and writing, "To the final episode of #KUWTK."

"I will never be able to put into words what does show and what you guys mean to me. Please know how much I love you!!!!! I try to show you guys how much you matter to me #KUWTK," Khloé wrote on Twitter, joking in another tweet, "I need therapy after this episode. I am sobbing #KUWTK."

Ryan Seacrest — who co-created the reality show, which premiered in 2007 — shared a throwback photo with the KarJenner family Thursday.

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"Tonight we say goodbye to a show that left an indelible mark on reality tv and pop culture," he wrote. "Thank you to the Kardashians and Jenners for allowing us to be a part of your family and to our friends at @BunimMurray who were there to document these special moments. #KUWTK."

"wow! great memories and blessings," Kendall Jenner wrote on Twitter, sharing Seacrest's post. Kylie also shared it, adding two heart emojis.

Re-sharing a fan's post asking how she was feeling about the finale, Kris Jenner wrote on Twitter: "It's such a mix of emotions. I'm so sad the show is ending but feel so blessed for all the love and support over the past 14 years."

Keeping Up with the Kardashians Kris Jenner, Kylie, Kendall, Khloe, Kim, Kourtney
Keeping Up with the Kardashians
| Credit: Miller Mobley/E! Entertainment

The Kardashians announced last September that the 20th season of KUWTK would be the last.

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"To our amazing fans - It is with heavy hearts that we've made the difficult decision as a family to say goodbye to Keeping Up with the Kardashians," their statement at the time began. "After what will be 14 years, 20 seasons, hundreds of episodes and numerous spin-off shows, we are beyond grateful to all of you who've watched us for all of these years – through the good times, the bad times, the happiness, the tears, and the many relationships and children. We'll forever cherish the wonderful memories and countless people we've met along the way."

Following the series finale, a special "Housewives-style" reunion will air with the cast, hosted by Andy Cohen and covering the entire series.

"Welcome to a sit down 20 seasons in the making," Cohen said in a teaser for the reunion. "For the first time ever, I'm grilling the Kardashian-Jenners."

The Keeping Up with the Kardashians series finale aired Thursday at 8 p.m. ET on E!, with the first part of the reunion following at the same time on June 17.