FILE - General view of the site of the Danube river in Vienna, Austria.
FILE - General view of the site of the Danube river in Vienna, Austria.

VIENNA - Vienna, Austria's elegant capital on the Danube river, has again been commended as offering the best quality of life of any city in the world; Baghdad, once more, was deemed the worst to live in.

The consulting firm Mercer said German and Swiss cities also performed well in its annual quality of living rankings. Zurich, Munich, Duesseldorf and Frankfurt remained in the top 10.

Mercer's survey helps companies and organizations determine compensation and hardship allowances for international staff. It uses dozens of criteria such as political stability, health care, education, crime, recreation and transport.

With a population of 1.7 million, Vienna topped the survey for the sixth year in a row, boasting a vibrant cultural scene alongside comprehensive health care and moderate housing costs.

The Austrian capital's extensive public transport system costs just 1 euro a day for an annual pass. Its Habsburg-era coffee houses, architecture, palaces, operas and other cultural institutions makes it a prime tourist destination.

Europe has seven of the world's top 10 cities in the 2015 survey. New Zealand, Australia and Canada each have a city in the top 10.

Baghdad, the Iraqi capital, was again ranked lowest in the world. Waves of sectarian violence have swept through the city since the American-led invasion in 2003.