Louis Tomlinson may be amazed by how quickly the years have passed, but One Direction’s music continues to hold a meaningful place in his life.

Thursday, July 23, marks 16 years since 1D was formed on X Factor, beginning one of the most successful boy band eras of the 2010s. To recognize the anniversary, the British singer and songwriter revisited several tracks from the group’s popular catalog through his Instagram Story, sharing his honest thoughts about each one. He began with the 2012 song “Moments.”

“So many special memories with this one,” Tomlinson wrote about the Up All Night track, which Ed Sheeran helped compose. “Absolutely classic @teddysphotos Melody. First time I ever felt really proud of my own vocal on track.”

When discussing “Na Na Na,” Tomlinson called it “Peak lyricism.” He offered another simple reaction to “Kiss You,” writing, “Always loved this one.”

“Not my fav but huge pop song,” he said about “Live While We’re Young,” which peaked at No. 3 on the Billboard Hot 100. “Still remember shooting the video clearly, some amazing memories that day!”

Tomlinson also highlighted songs that remind him of particular One Direction members. He explained that “Over Again” always “reminds me of Niall for some reason.”

“Pretty Sure this was when Liam first discovered his falsetto, I remember how proud we all were,” he wrote about “More Than This,” praising his late bandmate. “He sounds incredible!”

Following their beginnings on X Factor, Tomlinson, Niall Horan, Liam Payne, Harry Styles and Zayn Malik completed four sold out world tours, earned four No. 1 records on the Billboard 200 and placed six songs inside the Top 10 of the Billboard Hot 100. Their journey began July 23, 2010, after Simon Cowell asked the five contestants, who had each been eliminated as solo performers, to reenter the competition as a group.

A full decade has passed since 1D separated in 2016, and every member went on to establish a successful individual career. Tomlinson is now touring behind his latest solo record, How Did I Get Here?, which entered the Billboard 200 at No. 16 in February.

“Coming out of a band the size of One Direction, eyes are on you, and you’re expected to succeed instantly,” he told Billboard’s Jason Lipshutz for his January cover story. “Those things are normal to feel, but if you let it, it’ll steer you [toward] the wrong decisions. I’ve tried to come at this record with a bit more of a bird’s eye view.”