Ian Somerhalder: 'Happy Earth Day'

Ian Somerhalder rocks a bowler cap as he dines with friends at Gjelina Take Away on Sunday (April 22) in Venice Beach, Calif.

That same day, the 33-year-old Vampire Diaries star attended the launch of Kimberly Muller and Michael Muller‘s new book, Last Night I Swam With A Mermaid, in Santa Monica.

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“Happy Earth Day!!!!” Ian tweeted.

Last weekend, Ian and his girlfriend Nina Dobrev showed some PDA while taking a stroll on day three of the 2012 Coachella Music Festival.