The Duke of Cambridge will join thousands of bike fans at the Isle of Man TT for the spectacle of motorbike riders pitting themselves against the world famous circuit.
William, who is a keen rider, will watch as competitors take on the TT mountain course which is renowned for its difficulty and danger but inspires riders from across the globe. Two competitors have been killed during this year's event.
The duke will begin his day at the main grandstand watching the final stages of the TT Supersport Race 2 before attending a reception in the Government House tent.
Guests will include representatives from across the Isle of Man, including TT staff, volunteers, civic dignitaries and local businesses.
The Isle of Man TT was first staged in 1907 and is one of the oldest continuous motorsport events in the world.
It features riders competing in nine races, from a superbike category to sidecar events, in time trials around the circuit which is almost 38 miles long.
Wednesday will feature the second Supersport TT Race, the TT Zero for electric bikes and the Lightweight TT event.
Later, William will visit the the Joey Dunlop Foundation. Established in 2001 and named after the legendary TT racer, it creates specialist accommodation for visitors to the Isle of Man with a disability.