The “mobile borehole” was installed inside a manhole in the pedestrian zone of Aarau. A wooden platform with hole was built atop the manhole and atop the platform the yellow tent was set up against the rain.

fig. up: A cross section of the exploratory station with vertigo-technology [mobile borehole] hidden inside the manhole for a probe dive up to 120m into the depths.

Probe operators in Aarau