Groundwater flow in shallow rock aquifers in Brittany, France was studied using CFC age data. The researchers found that groundwater travel distances were influenced by topography in lowland areas and recharge rate in upland areas. Groundwater flow was mainly controlled by topography in lowlands and by recharge rate in uplands. The study showed that groundwater flow paths were relatively old and local, with a mean travel distance of 350 meters and a mean CFC age of 40 years. The findings suggest that topographical and hydrological factors play a significant role in determining groundwater circulation patterns in the studied aquifer.