Wales' biggest hospital has accepted its first 12 patients.
The temporary 2,000-bed Dragon's Heart Hospital, inside the Principality Stadium, aims to ease the pressure on the NHS amid the coronavirus pandemic.
The field hospital, which was opened by Prince Charles last week, is the second biggest in the UK behind London's Nightingale hospital.
Cardiff and Vale University Health Board (CAVUHB) said more patients would be admitted later this week.
The health board said patients were being transferred from University Hospital of Wales (UHW) and University Hospital Llandough, both in Cardiff.