VIRGO is a european project of gravitational waves detector (photo INFN/CNRS: site in construction at Cascina, near Pisa, Italy)
The project consists in a laser Michelson interferometre with two orthogonal arms 3 kms long. The effective length of the optical path is 120 km.
The frequency domain goes from 10 to 6000 Hz; this should allow the detection of the waves produced by the supernovae and the coalescence of binary systems in the galaxy or further, as in Virgo galaxy cluster.

VIRGO project