The Great Dorset Steam Fair (abbreviated GDSF, and since 2010 also known as The National Heritage Show) is an annual show featuring steam-powered vehicles and machinery. It now covers 600 acres (2.4 km2) and runs for five days. It is reputedly the largest collection of steam and vintage equipment to be seen anywhere in the world. The fair was founded by the Dorset Steam & Historic Vehicle Club, and has been held in Dorset, England, every summer since 1969.

The fair now attracts up to 200,000 visitors. [Wikipedia]