Well drilling is a specialized methodological concept within nuclear engineering and related fields concerning the precise creation of bores or access pathways within materials or structures integral to nuclear processes or environments. This domain investigates the techniques, challenges, and implications of fabricating such features under demanding conditions, considering material properties, radiation effects, and thermal loads. Its significance lies in enabling essential functions such as instrumentation deployment, fuel element design validation, experimental access, and post-irradiation examination, thereby supporting the research, development, and safe operation of nuclear systems.