There are so many things about the Shroud of Turin that suggest against the possibility that it is some kind of forgery. Despite our technological advancement, no one has been able to actually make one, while those who argue against its authenticity maintain that it is a medieval forgery. Fine. Just make one. Don’t even limit yourself to the materials available in the Middle Ages. Go ahead. Try it.
Thing is, the shroud contains things like pollens from plants that are only indigenous to the Middle East and not Europe. No one in the Middle Ages knew anything about microscopic particles. The image printed on the shroud cannot be explained. It wasn’t made using ink or paint, because the coloration is embedded through the fibers of the cloth itself, and not just on the surface as it would be with paint. The positioning of the nail marks at the wrist and ankles is inconsistent with depictions of the crucifixion, where the nails are placed in the hands and feet. The blood on the shroud belongs to a human male. Again, a medieval forger would have had no idea that modern science would be able to distinguish between human and animal blood.
There’s a thousand more things, each more interesting than the last. Most recently, a new study undertaken by a group of European scientists indicates that the man on the shroud “dislocated” arms and paralysis of his right arm, resulting in an otherwise peculiar placement of the arms across the body during burial.