Last week we have started to unbox, place and assemble the Underground Argon (UAr) Cryogenic System for DarkSide-20k (DS-20k) underground at the Laboratori Nazionali del Gran Sasso (LNGS), Italy, which was shipped from CERN end of last year after its successful benchmarking. All heavy items are in place and connected, and interfaces with the lab have been identified. We will continue the testing of the cryo-system at LNGS, in particular with a modified heat exchanger geometry for argon boil-off, before the system will be used for a mechanical mockup test of DS-20k.