Higashi Koya-kaido road passed through the foot of the Ikoma mountain range bypassing the rivers in the Yodo-gawa River system and wetlands which used to exist around Lake Kawachi (Fukano-ike pond), and ran along the left bank of the Ishi-kawa River after crossing the Yamato-gawa River around Kawachi-Kokufu (presently, Fujiidera City).
淀川水系の河川や、かつて存在した巨大な河内湖（深野池）周辺の湿地帯を避けて生駒山地の麓を通り、河内国府（現在の藤井寺市）付近で大和川を越えると石川(大阪府)の左岸に沿って通った。