In this study, the Golgi method for light microscopy, transmission and conventional scanning electron microscopy, the ethanol-cryofracturing technique, the freeze-fracture method for SEM, and the freeze-etching method have been used in conjunction to analyze the three-dimensional cytoarchitectonic arrangement and intracortical circuits of vertebrate cerebellar cortex. Approximately more than 100 specimens of mice, rat, teleost fishes and human cerebelli were processed by the above mentioned techniques. A chronological review of other methods for studying hidden surfaces of cerebellar nerve cell has been also described. The three-dimensional morphology, outer and inner surfaces of granule, Golgi, Purkinje and stellate cells were reviewed by means of a correlative and comparative study. The cerebellar circuits formed by mossy and climbing fibers with granule cell dendrites and Purkinje cell-granule cell synapses have been traced by ethanol-cryofracturing technique, freeze-fracture method for SEM and freeze-etching technique. These findings have been correlated with previous light and electron microscope findings published in the last century. Some advantages and limitations of each method are pointed out. The review emphasizes the paramount importance of correlating light microscope Golgi method with ethanol-cryofracturing and slicing techniques for SEM. The correlation between freeze-fracture method for SEM and freeze-etching technique provides a new approach for studying three-dimensional morphology of nerve cells at cellular and macromolecular levels. This modern methodology of three-dimensional analysis offers new potential areas for future experimental investigation in embryology and pathology of the central nervous system
