This case study considers a Finnish example of replacing overhead lines with underground cabling. The same strategy is also applied in other European countries. Elenia is the second largest electricity distribution system operator in Finland. To adhere to the outage requirements of Finland’s updated Electricity Market Act, distribution system operators such as Elenia are investing substantially in underground cabling. This is in line with expected impacts of climate change, including increased frequency and intensity of precipitation events (in particular storms and snow loads) as well as increased growth and age of trees relating to increasing temperatures, resulting in higher amounts of deadwood. Temperature increase due to climate change is expected to cause deciduous trees to remain in leaf longer, increasing the risk of falling trees and resultant damage to power lines. In many cases, underground cabling efforts have been aligned with the installation of fibre-optic cables by telecommunications companies, in so-called “co-construction” efforts for cost-minimisation. Elenia itself has a target to achieve 75% underground cabling of its network by 2028. Underground cabling contributes to climate change adaptation of the energy system, resulting in secure energy supply.