Some 125 stone plaques in Rome mark inundations dating back 800 years. We trace the rise and fall of the Tiber using the tools of geodesy. We introduce the quantitative geoscience of measuring Earth's shape, deformation, and its gravity field. Lectures on fundamental principles and programming exercises prepare for outdoor on-campus field-work and the mandatory week-long research trip to Italy. In Rome, we measure and map the elevation of known historical flood markers, placing them in the chronological context of urbanization, interpreting them in the light of humanity's attempts to control nature.