The Alnwick Poison Gardens in Alnwick, England was established in 2005 by the Duchess of Northumberland. The grounds contain nearly 100 deadly plants that produce poisons or hallucinogens. Some are so dangerous, they are displayed only behind glass. And yes, there are opium poppies, cannabis, and magic mushrooms as well, but you can't get close to them. Read about the poison gardens and other strange gardens that are (or once were) open to the public around the world in a list called Gardens of Death and Other Horticultural Marvels at Atlas Obscura. Link

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