Bryennios had camped at the plain of Kedoktos (a name deriving from the Latin aquaeductus) on the road to Constantinople.
Alexios's forces set forth from Constantinople and camped on the shore of the river Halmyros-a small stream between Herakleia (modern Marmara Ereğlisi) and Selymbria (modern Silivri), modern Kalivri Dere-near the fort of Kalavrye (, modern Yolçatı) [REF].