The cerebellar peduncles are three paired bundles of fibres that connect the cerebellum to the brainstem.
The superior cerebellar peduncles are bundles of white matter that connect the cerebellum to the midbrain. The middle cerebellar peduncles connect the cerebellum to the pons and are composed primarily of afferent fibers. The inferior cerebellar peduncles are thick rope-like strands emerging from the posteriolateral aspect of the upper medulla oblongata.
The peduncles form the lateral border of the fourth ventricle, and form a distinctive diamond the middle peduncle forming the central corners of the diamond, while the superior and inferior peduncles form the superior and inferior edges, respectively.
See also Anatomy of the cerebellum#Peduncles
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