The Poison Garden slumbers behind black iron gates within the Alnwick Garden in northern England. The gardens are part of the land that surrounds Alnwick Castle, which fans of Harry Potter may recognize from the scene where the kids learn how to fly on their brooms. The Poison Garden was conceptualized by the Duchess of Northumberland, Jane Percy, who wanted to create something unique that would be a true attraction for visitors.

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With over 600,000 visitors to the garden each year Percy has certainly achieved that goal. And those visitors are warned not to smell, touch, or taste any of these dangerous plants. Check out the list below to see what other interesting things visitors will discover at the Alnwick Poison Garden.

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There are 100 varieties of poisonous plants that grow within the Poison Garden. When Jane Percy was creating her garden, she wanted to make sure these plants would tell a story. That visitors would be enticed to learn about the plants that they might otherwise have passed right by. One such plant is a favorite of the duchess, Brugmansia, or angel's trumpet. These plants were often found in glasshouse gardens in Victorian England. It’s said that while taking tea, ladies would let the nectar from the blooms drip into their tea. The ladies would experience feelings similar to LSD. That sort of does away with the idea of a fainting Victorian lady.

9 Special Permission

Many of the plants that grow in the Poison Garden have to be approved, with special permission from the government, to be grown. Plants like opium poppies, magic mushrooms, and cannabis, to name a few. Part of Jane Percy’s goal with this garden is to educate children on how plants can kill and uses that as an anti-drug message.

8 When Inspiration Strikes

Jane Percy took a lot of inspiration from the Medici poison garden in Italy. Found in the Padua Botanical Garden, which is the world’s first university botanical garden, which was designed for the purpose of growing medicinal plants. The Duchess’s trip to an archeological site in Scotland also reinforced her idea to create the Poison Garden.

7 Approach With Caution

Although there are many reminders not to touch, taste, or smell any of the plants within the Poison Garden, merely being in close proximity can also be dangerous. During the summer, in 2014, several visitors fainted due to fumes from the garden.

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The gates that guard the garden entry state very clearly that the plants can kill and are accompanied by a skull and cross symbol. For their safety guests are not allowed to walk through the garden on their own. However, there are tours available which explain the different types of plants and their properties

6 Look But Don’t Touch

Some of the plants that grow in the Poison Garden are so deadly they are kept within cages, including the coca and cannabis plants. Ensuring that tourists don’t get close enough to harm themselves or perhaps try to take some of the deadly plants. The garden is also under 24-hour security. The groundskeepers have to wear protective gloves when seeing to this part of the Alnwick Gardens and are specially trained to handle the large variety of harmful plants.

5 From Tuileries to Poison

When Jane Percy set out to revive the gardens of Alnwick castle she wanted someone to take her unique and intriguing ideas and make them into reality. She found Belgian landscape architect Jacques Wirtz who had won acclaim for the redesign of part of the Tuileries in Paris. Wirtz has been compared to the man who designed the gardens at Versailles, André Le Nôtre and this unique project certainly shows his spectacular talent.

4 Famous For More Than Poison

The Poison Garden might be the most fascinating part of Alnwick Castle but the Castle itself is also famous. The castle appears in the first and second Harry Potter films standing in for Hogwarts.

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In the first film, the gang of first years learned how to ride their brooms with the castle behind them. In the second film, Ron and Harry crash into the Whomping willow while Alnwick Castle appears in the background. The castle has also been used for a location in Downton Abbey and the film Transformers: The Last Knight.

3 Common Killers

What many visitors to the Poison Garden find fascinating is how common plants that they encounter every day can be toxic and deadly. One example appears in nearly all English gardens—the laurel hedge. This abundant plant is incredibly toxic if ingested and can cause serious illness or even death. Fallen leaves or those that are wilted are the most toxic and need to be handled with care. Cutting into the wood of the laurels can release fumes and also cause poisoning. The Poison Garden has educated many on the dangers of a plant that appears in many a garden.

2 Come, Little Children

The Duchess didn’t have plans of luring children into her garden. Okay, actually she did. But her aim was to educate, nothing nefarious. Jane Percy felt that children would be more interested in learning about how a plant could kill you or how gruesome a death might be after ingesting one of the toxic residents of her garden, then they would be to learn about typical horticulture. By twisting the concept of the garden, she was able to provide a place where children, and adults, would want to learn all about the different properties of a plant. That’s some sly thinking.

1 All Shapes and Varieties

Some of the most interesting plants found in the Poison Garden include Hemlock, Digitalis, Deadly Nightshade, and Strychnos nux-vomica. Many of these names will sound familiar to anyone who loves a good murder mystery. Hemlock killed Socrates and in ancient Greece, it was used to kill prisoners. Digitalis, also known as Foxglove, can be used to treat heart conditions, but too much of a good thing can be deadly. As is the case with this plant. Deadly Nightshade, or Belladona, is one of the most toxic plants in the world although interestingly cattle and rabbits can eat the plant without any side effects. Strychnos nux-vomica is the source of strychnine which can be deadly if inhaled.

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