Josh Radnor is taking a look down memory lane.

In honor of the 20th anniversary of “How I Met Your Mother,” Radnor, who starred as Ted in the show, shared behind-the-scenes pictures of him and the cast in the “early years” of filming the series.

The post came exactly 20 years after the pilot episode aired on CBS on Sept. 19, 2005.

In one snap, Neil Patrick Harris and Alyson Hannigan participate in a table read, and in another photo, Hannigan and Cobie Smulders share a hug while on set for the show’s famous bar, MacLaren’s Pub.

There were also a few pics of everyone having fun on set. Radnor shared a snap of him and Smulders standing in a bathtub and another picture of him and Jason Segel almost falling off a couch.

In the caption, he talked about how much the show, which ran until 2014, meant to him.

“Apparently (astonishingly) ‘How I Met Your Mother’ premiered twenty years ago today. Here are some pics from the early years,” he wrote.

“I cannot overstate how much I’m enjoying rewatching the show, strolling down memory lane, and breaking down each episode,” he added, referring to his podcast, “How We Made Your Mother.”

“We made a show about a man looking back on a pivotal time in his life and the life of his dearest friends. And now all these years later we’re looking back on this pivotal time in our own lives (when we were making a show about a pivotal time in these characters’ lives…),” he added. “It’s been such a treat to fully appreciate what a brilliant, funny, touching show I was a part of.”

“How I Met Your Mother” starred Radnor as Ted, Harris as Barney, Smulders as Robin, Hannigan as Lily and Segel as Marshall.

The sitcom’s premise follows a father who recalls the hilarious yet loving story of how he met his children’s mother. It wasn’t until the Season 8 finale that “the mother” was revealed to be a woman named Tracy, played by Cristin Milioti.

“My comfort show, I love you guys so much,” one person commented on Radnor’s post.

“in my head, this is my second family,” another wrote.

“I’m crying right now. Time flies,” a third said. “It’s the 20th anniversary of the best TV series in the world.”