The authors have presented the less known CSF alternative pathways. Besides the CSF absorption into blood vessels in arachnoidal villi alongside venous sinuses there is additional CSF outflow to the lymphatic vessels. For many years the neurophysiologists did not take into account and did not appreciate this route despite it had been in XIX-th century. In those times Schwalbe noticed that after Berlin blue injection into the cranial subarachnoid space of exsanguinated rabbits and dogs the markers uptake increased in the local cervical lymphatic nodes. The review contains a structural description as well as a physiological explanation of the alternative CSF outflow. The paper also shows the development of views or: this topic. The prelymphatic cerebral vessels described by Gasley-Smith and perineural lymphatic pathways around cranial and spinal nerves seem to be the most significant ones connecting the central nervous system and the lymphatic system. It has been proved during animal experiments, that 20-30% CSF flows through the alternative pathways. It is too early, to come to the final conclusions. But the present results concerning CSF outflow to the lymphatic system can confirm its influence on the CNS immunology, hydrocephalus and pseudotumour cerebri aetiology and olfactory sensation (the flow of the fluid might help to remove the odor-stimulating molecules).