This book contains four substantial studies scrutinising aspects of the evidence for the design and form of the curtain, milecastles and turrets of Hadrian's Wall as preserved in the primary archaeological record. Together they constitute a fresh assessment of the original appearance of the Wall and its structures, a matter of long-running controversy since nowhere does any part of the Wall survive to full height. The nature of the top of the curtain, and the form of superstructures over milecastle gateways, are not simply structural details of merely academic interest: the contributors show that both have a profound impact on how we interpret the function of the linear barrier both in its initial conception and as used over three centuries by the Roman army.