Millions have fled their homes since the civil war began in Syria four years ago.
This year, refugees in their hundreds of thousands have tried desperately to enter countries in Europe, causing an unprecedented crisis through their sheer numbers.
To put a human face on the tragedy, the organisers of Inside Out Austria pasted the photographs of 2,100 refugees on a 300m strip in a shopping street in Vienna. A mass demonstration over the weekend drew 10,000 participants, despite sharp criticism from a local politician about "property damage".
Asking for donations, to be channelled to the refugees, organisers said the project - a Walk of Fame of Humanity - wanted the public to perceive refugees as people, not numbers, and welcome them.