It usually takes several hours from Siyang to Sihong.

Without a private car, 1.30 hours is not enough. My girlfriend's home is in Siyang, and I am in Sihong. I usually take the route of Sihong-Jeffery Ji-Yanghe-Siyang, which takes at least two hours. Her home is in Wang Ji, so I often go there for nearly three hours! It's faster to take S245, as upstairs said, "drive by yourself" for more than half an hour.