  In the context of the PTOLEMY project, the need for a site with a rather low
cosmogenic induced background led us to measure the differential muon flux
inside the bunker of Monte Soratte, located about 50~km north of Rome (Italy).
The measurement was performed with the Cosmic Ray Cube (CRC), a portable
tracking device. The simple operation of the Cosmic Ray Cube was crucial to
finalise the measurements, as they were carried out during the COVID-19
lockdown and in a site devoid of scientific equipment. The muon flux measured
at the Soratte hypogeum is above two orders of magnitude lower than the flux
observed on the surface, suggesting the possible use of the Mt. Soratte bunker
for hosting astroparticle physics experiments requiring a low environmental
background.
