As you step into this walled oasis of botanical wonder, created by the Apothecaries' Society in 1673 for students studying medicinal plants and healing, you may come across a few wandering ducks. One of the oldest of its kind in Europe, the small grounds are home to an eclectic assortment of botany, from carnivorous pitcher plants to vibrant yellow flag irises, a cork oak from Portugal, the largest outdoor fruiting olive tree in the British Isles, and numerous rare shrubs and trees.