Deciphering the large-scale environment of radio galaxies in the local
  Universe: where do they born, grow and die?
  The role played by the large-scale environment on the nuclear activity of
radio galaxies (RGs), is still not completely understood. Accretion mode, jet
power and galaxy evolution are connected with their large-scale environment
from tens to hundreds of kpc. Here we present a detailed, statistical, analysis
of the large-scale environment for two samples of RGs up to redshifts
$z_\mathrm{src}$=0.15. The main advantages of our study, with respect to those
already present in the literature, are due to the extremely homogeneous
selection criteria of catalogs adopted to perform our investigation. This is
also coupled with the use of several clustering algorithms. We performed a
direct search of galaxy-rich environments around RGs using them as beacon. To
perform this study we also developed a new method that does not appear to
suffer by a strong $z_\mathrm{src}$ dependence as other algorithms. We conclude
that, despite their radio morphological (FR\,I $vs$ FR\,II) and/or their
optical (HERG $vs$ LERG) classification, RGs in the local Universe tend to live
in galaxy-rich large-scale environments having similar characteristics and
richness. We highlight that the fraction of FR\,Is-LERG, inhabiting galaxy rich
environments, appears larger than that of FR\,IIs-LERG. We also found that 5
out of 7 FR\,II-HERGs, with $z_\mathrm{src}\leq$0.11, lie in groups/clusters of
galaxies. However, we recognize that, despite the high level of completeness of
our catalogs, when restricting to the local Universe, the low number of HERGs
($\sim$10\% of the total FR\,IIs investigated) prevent us to make a strong
statistical conclusion about this source class.
