Holby is a fictional city in the United Kingdom, the setting for the BBC medical dramas Casualty and Holby City, and the police drama HolbyBlue. It is based on the real city of Bristol, where Casualty was formerly filmed, and is notionally located in the fictional county of Wyvern in South West England, not far from the border with Wales. While Casualty has been filmed in Cardiff since 2011, Holby City is filmed in Elstree, Hertfordshire. Both shows are set in the same fictional Holby City Hospital. Holby has an airport called Holby International.