Urban environments provide many challenges to conventional geophysical sensing. These can include the density of structures on the surface, subterranean infrastructure, electrical noise, pedestrian traffic, vehicular traffic, air traffic, and waterborne traffic in some cases. Surface access for data collection also can be an issue as more of the area is covered in concrete or asphalt or is impacted by traffic. Although challenges exist, there are also new opportunities as technology advances and as more parts of our daily lives become digitally intertwined. The papers in this special section highlight different geophysical sensing applications, ranging from infrasound to distributed acoustic sensing (DAS), that take advantage of the additional energy sources in more densely populated areas, optimize data collection around times of peak noise, and adapt to the dynamic environment that urban settings present.