The paper describes the results of a study of the nails from the Roman legionary fortress at Inchtulhil, Perthshire. The nails were shown to be divided into six main groups, the classification being based on type of head (pyramid or disk), length, and dimensions of the die used for forming the head (determined by measurement of the section of the shank). Metallographical examination revealed that the iron of the nails was heterogeneous in character, being composed of regions of high and low carbon content. The examination also showed that a tapered blank was first forged from the bloom; this was then reheated and the head was by forging in a die. The fact that the larger nails appeared to have a higher proportional of high-carbon material in their structure suggested that some selection may have been intended.