The Swamp of Tamir

The treacherous swamp on the continent of Tanalore where the Magical Fruit grew. Rosella had to traverse the troll's caves to reach it. It was made up of long stretches of quicksand, large trees, and with only a few small islands scattered throughout. A cobra was on one of the islands guarding the Magical Fruit.

Real world
The term Death Bogs of Tamir comes from a death narration in King's Quest 6, if you choose to eat a part of the nightshade bush.

It may be influenced by the Greek legend of the garden of Hesperides, in which an immortality giving golden apple tree or trees grew and were guarded by a snake (or dragon in some versions of the story).

It may also be inspired by ideas from the bible, referencing the fruit of wisdom, the snake/Eve, and also the 'cave', the 'portal' which the bible speaks of Eve and Adam escaped through.

Additionally there are other legends of magical fruit trees in eastern myths as well, which may be basis for the story, such as immortality giving magical peaches or pears.