Blake Lively is looking back on her past fondly.

“The summer gossip girl turned 18…,” Lively, 38, wrote via instagram on Sunday, September 21, reflecting on the 18th anniversary of her hit series, Gossip Girl.

“This show was my college. It was my education, my social life, my hardwork, my late nights and early mornings, my teacher,” she continued. “New York City and Silvercup Studios (& sometimes Paris ) was my campus for SIX years.”

She added, “So many memories. What. A. Decade. What a University.” Lively also included a series of throwback photos from the show’s set, including a large ensemble photo as well as snaps with several of her costars, including Leighton Meester and Penn Badgley.

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