Seven-times world champion Lewis Hamilton, Formula One's most successful driver of all time, arrived for his first day at Ferrari on Monday, and said it was a dream come true to race for the Italian team.

Almost a year since Hamilton announced his shock decision to leave Mercedes, where he won six of his seven Formula One world championships, for Ferrari, the 40-year-old is at the team's headquarters at Maranello for his first official day.

"There are some days that you know you'll remember forever and today, my first as a Ferrari driver, is one of those days," Hamilton wrote on Instagram.

"I've been lucky enough to have achieved things in my career I never thought possible, but part of me has always held on to that dream of racing in red. I couldn't be happier to realize that dream today."

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Hamilton's first day included a seat fitting followed by the simulator, but due to weather conditions he is not likely to have a first outing at the Fiorano test track until Wednesday, while official testing starts in Bahrain over Feb 26-28.

The Briton had his worst season in Formula One last year, in terms of championship position, finishing seventh overall but did win two races after two seasons without a victory. Hamilton's last championship win came in 2020.

Hamilton will partner Charles Leclerc at Ferrari, who are without a driver's title since 2007, taking the place of Spaniard Carlos Sainz who has joined Williams, and the 2025 season begins with the Australian GP over March 14-16.

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"Today we start a new era in the history of this iconic team, and I can't wait to see what story we will write together," Hamilton added.