The White Truffle (Tuber magnum pico) is the world's most expensive edible fungus, fetching up to U$3,000 per kilo. They can only be found in the Italian regions of Piedmont, Emilia-Romagna, Tuscany and Marches, and the Istrian peninsula of Croatia, and because they grow about a foot underground, they can only be located with the help of trained dogs.
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