Opening up the subsurface for the cities of tomorrow. Considering the access to subsurface knowledge - Evaluation of practices and techniques: TU1206 COST Sub-Urban WG2 Report

The subsurface is an important constituent of the physical environment of cities. We live on top of it; building and construction have to deal with the structure and properties of the subsurface, and occasionally with the hazards it presents; and we benefit from, and in some cases are dependent, on many of its ecosystem services. Cities not only expand outward and upward, but also downward. More and more, subsurface space is being used to relieve the increasingly crowded and congested urban surface. The more use we make of subsurface space, the more surface space we free up for the one function that cannot do without daylight and fresh air: living.