Walls of Constantinople
The four main crusader armies left Europe around the appointed time in August 1096. They took different routes to Constantinople, some through Eastern Europe and the Balkans, some crossing the Adriatic Sea. Coloman of Hungary allowed Godfrey and his troops to cross Hungary only after his brother, Baldwin was offered as a hostage to guarantee his troops' good conduct. They gathered outside the Roman-era Walls of Constantinople between November 1096 and April 1097. Hugh of Vermandois arrived first, followed by Godfrey, Raymond, and Bohemond.