  The Southern Wide-field Gamma-ray Observatory (SWGO) is a project by
scientists and engineers from 14 countries and 78 institutions to design and
build the first wide-field, ground-based gamma-ray observatory in the Southern
Hemisphere, with high duty cycle and covering an energy range rom hundreds of
GeV to the PeV scale. The observatory will cover the Southern sky and aims to
map the Galaxy's large-scale emission, as well as detecting transient and
variable phenomena. The host sites under consideration are at a minimum
altitude of 4400 m.a.s.l. and comprise two types: flat plateaus of at least 1
km$^{2}$ for the installation of an array of tank-based water Cherenkov
detectors (WCD), or large natural lakes for the direct deployment of WCD units.
Four South American countries proposed excellent sites to host the observatory
meeting these requirements. Argentina proposed two locations in the Salta
province, Bolivia presented one site in Chacaltaya, Chile two locations within
the Atacama Astronomical Park, and Peru two ground-based locations in the
Arequipa district as well as lakes in the Cuzco region. The SWGO collaboration
is currently conducting a site characterization study, gathering all the
necessary information for site shortlisting and final site selection by the end
of 2023. The process has reached the shortlisting phase, in which primary and
backup sites for each country have been identified. The primary sites were
visited by a team of experts from the collaboration, to investigate and
validate the proposed site characteristics. Here we present an update on these
site selection activities.
