The dpa news agency reported that a few hundred people gathered for the demonstration today, with placards such as "Together against terror" and "Hatred makes the earth hell," and the crowd later grew to over 1,000.
The organizers had expected several thousand protesters.
The country's biggest Islamic association had refused to take part in the march. The Turkish-Islamic Union argued it would send the wrong signal by suggesting that international terrorism is mainly a Muslim problem. It also said Muslims observing the Ramadan fast couldn't be expected to march for hours in summer temperatures.