I have come across a claim that in early Islam, the focal point of orientation for prayers was not Mecca but was originally supposed to be Petra, and that originally Qiblas used to point in that direction.
I found this book by Dan Gibson that makes this claim: Early Islamic Qiblas: A survey of mosques built between 1AH/622 C.E. and 263 AH/876 C.E (WorldCat). He is the only person I could find that says this.
How credible is this claim and how credible is Dan Gibson as a historian?