Vienna, Austria ranked as best city in the world by Mercer Consulting group

For the third year in a row Vienna, Austria has been rated as the best place to live in the world.

The Austrian capital, with its ornate buildings, public parks, extensive bicycle network, and great art offerings recently reduced the cost of public transport tickets.

Serious crime is rare in Vienna. About 1.7 million people call it home.

Swiss and German cities did well on the survey compiled by Mercer, a consulting group. More than half the cities in the top 25 are in Europe

Athens ranked among the lowest in Europe in personal safety.

Oslo, Norway fell because of the recent mass killings there.

Baghdad is ranked the lowest city in the world for quality of life.

The highest-ranked U.S. city was Honolulu, which ranked 29th.

San Francisco was tied for 30th with Adelaide, Australia.