The Folk Of The Faraway Tree by Enid Blyton

Three children discover an enormous, enchanted tree in a nearby wood whose branches lead up to ever-changing magical lands; they befriend the tree’s eccentric inhabitants—cheerful, oddball characters who live among the branches—and together the group climbs into one wonderous or dangerous land after another, outwitting wicked foes, helping friends, and learning bravery and kindness through a series of lighthearted, imaginative adventures.

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