  ArDM-1t is the first operating ton-scale liquid argon detector for direct
search of Dark Matter particles. Developed at CERN as Recognized Experiment
RE18, the experiment has been approved in 2010 to be installed in the Spanish
underground site LSC (Laboratorio Subterraneo de Canfranc). Under the label of
LSC EXP-08-2010 the ArDM detector underwent an intensive period of technical
completion and safety approval until the recent filling of the target vessel
with almost 2 ton of liquid argon. This report describes the experimental
achievements during commissioning of ArDM and the transition into a stage of
first physics data taking in single phase operational mode. We present
preliminary observations from this run. A first indication for the background
discrimination power of LAr detectors at the ton-scale is shown. We present an
outlook for completing the detector with the electric drift field and upgrade
of the scintillation light readout system with novel detector modules based on
SiPMs in order to improve the light yield.
