Thalamocortical fibers are the main source of subcortical information for the cerebral cortex. The development of thalamocortical connections is a major neurodevelopmental event that enables formation of a structural basis for a variety of sensory sensations, including pain. The interaction of thalamocortical fibers and transient fetal zones plays a key role in this process. Importantly, changes in cell aggregation and differentiation in the thalamus and cortical plate closely reflect the growth of thalamocortical axons. This study aims to investigate the development of the ventroposterolateral region of the thalamus, as well as somatosensory cortex, to provide reliable structural indicators of differentiation of the thalamocortical system. Here we used postmortem fetal brains aged 7.5- 36. PCW processed by histological, immunohistochemical, and in vitro MRI methods. The growth of thalamocortical fibers is a complex process, that needs to be studied through development, from the embryonic period until the late fetal period. Our results indicate early (7.5 PCW) outgrowth of thalamocortical fibers located in the ventrolateral part of the thalamus. Thalamic territories were detected between 9- 10 PCW. We confirmed that AChE and CD15 immunohistochemical staining are the most prominent markers for the future ventrolateral area. We show that between the 12th and 14th PCW, the fibers grow within the deeper layers of the intermediate zone and enter the cortical plate, in parallel with the expansion of the subplate zone. After that, the close interaction of thalamocorticals with the colossal fibers begins, as well as the „waiting period" in the subplate zone. The VP nucleus is delineated from the 15th PCW and its further cytoarchitectonic maturation is detected. Fibers accumulate in the superficial areas of the subplate zone just below the future somatosensory cortex from the 19th PCW. Penetration of thalamocortical fibers into the cortical plate (at approximately 24th PCW) follows the initial lamination of the cortical plate, were detected with AChE, MAP2, Nissl and in vitro MRI. Finally, cortical plate shows a basic six-layered pattern between the 25th and 34th PCW. Our results show that the main features of growing halamocortical fibers are fan-shaped radiation to the lateral, a short path through the sagittal strata and interdigitation with colossal fibers. In addition, the ventroposterolateral region of the thalamus differentiates before the somatosensory cortex. Importantly, the highest degree of cytoarchitectonic differentiation occurs around the 27th PCW, followed by an exponential development trend that coincides with the phase of intensive synaptogenesis in the cortex. Data on the spatio-temporal development of thalamocortical fibers, transient fetal zones and cortical plate are important for considering thalamic vulnerability and functional maturation of the somatosensory thalamocortical system, including issues related to pain sensation during the fetal period.