Blue Peter presenter Simon Thomas has announced he's leaving the show.
Simon, 31, said he wanted to go after new challenges after fronting 550 episodes of the top CBBC show since joining in January 1999.
He said: "It was a tough decision to make because Blue Peter is a place where you get to fulfil your dreams - and I've certainly done that."
He's going to make his last appearance on 25 April, when the current series comes to an end.
His highlights have included climbing Mount Kilimanjaro, freefall parachuting with the RAF, competing in the indoor athletics championships and sparring with Olympic boxing hero Amir Khan.
He also presented the Queen with a gold Blue Peter badge when she visited the studios.
Blue Peter editor Richard Marson said: "Simon will be a tough act to follow. We wish him the very best for the future."