How long did it take a camel rider to travel from Chengdu to Mesopotamia?

I remember reading something to the effect that a typical journey along the Silk Road by camel from the ancient Chinese capital Chengdu to Mesopotamia or that region took about 6 weeks. At least I remember it that way. I’m not sure now. Could it have been 6 months? Does anyone know? I look forward to your feedback.

Google earth says it’s roughly 4,000 miles from Baghdad to Beijing. Assuming 20 miles a day, that’s 200 days. 30 miles a day, 133 days. Even allowing for Chengdu shaving 1000 miles off it, that’s still a long road.

To do the trip in six weeks, or 42 days, you’d be doing 100 miles a day. Perhaps you read “6 months”?

Yes. 6 months sounds more reasonable.