RA-Dec distribution of galaxies within the area we targeted by VIMOS observations, indicated by the green outline. Black dots represent galaxies of the 30-COSMOS photometric catalog with 0.60 ≤ z_phot ≤ 0.86, while red dots (and the underlying gray contours) represent galaxies from the 20 K-sample in the range 0.72 ≤ z_spec ≤ 0.74. It is possible to see the presence of a significant galaxy concentration and of two long filamentary structures pointing toward it.