I admit to not knowing all that much about Islam beyond what I was taught in R.E. lessons at school. So I knew about Mohammed and some of the traditions, and that’s pretty much it. So this Reclusive Leftist post on facts about Islam is most enlightening:
There is no archaeological or written evidence that Mecca as traditionally described even existed at the time of Mohammed. It may have been a small village, but it was not a trading post or settlement of any size.
There are plenty more.