It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Prince Charles Praises Poundbury Students
The Prince of Wales has praised former students of his architectural institution and described his joy at seeing them working on one of his most important building projects in Dorset.
Alumni from the Prince's Foundation for the Built Environment are helping to design the latest phase of Poundbury - Charles' model village.
Charles is well known as a champion of traditional architectural styles over modernist designs and has tried to implement his ideas in the development which is an extension to Dorchester.
Surrounded by past graduates at the Foundation's offices in Shoreditch East London, Charles gave a speech to mark their efforts and defended the project describing the economic benefits it had brought to the area.
He said that despite the "brick bats'' he had faced, businesses were starting up and a survey commissioned last year had stated Poundbury had contributed more than £800 million to the local economy.
The heir to the throne said: "How rewarding it is for me to see the entire phase two being designed by a majority of my alumni... that gives me more pleasure than anything else.''
The Prince later broadened his comments to cover urban developments in general, saying: "The greatest challenge is mass urbanisation on a vast scale, without any proper thought to what the future will hold.''
Charles was joined for part of his visit by King Jigme Khesar Namgyel Wangchuck of Bhutan - the Himalayan Kingdom - and his wife Queen Jetsun, the daughter of an airline pilot, who had tea with Charles and the Duchess of Cornwall at Clarence House on Wednesday.
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Anne-Marie Ellement took her own life after claiming she'd been raped by two colleagues.
48 Zany Zebras sculptures were sold off to raise money for Marwell Zoo.
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