Battlefield archeology is a fairly new discipline and focuses on finding the location of an ancient battlefield which can often be extremely difficult.
As there were no permanent structures until the introduction of trench warfare the location of a battle site would be researched using the natural environment, geographical location and environmental archeology.
Before the use of firearms, the nature of ancient warfare meant that there was a closer bodily proximity, it meant therefore that the area of conflict was relatively small. Ancient weapons were highly prized and personal to the combatants. This meant that there was less likelihood that they would be left on the battlefield. As these ancient battles were fought on the surface, it would have been cleared and any material used was then recycled.
To assess the location of a battlefield there are various other approaches that can be made in spite of the lack of hard evidence in the form of artifacts.
A study of the literature at that time can be insightful. If we learn about the likely approach routes and the size of the armies and the type of weaponry used and the tactics employed we can then study the ancient landscape to assess likely sites.
Core samples are taken to assess the composition of the land. For example if the core sample shows a marshy environment then the area would have been totally unsuitable for fighting a battle.
Metal survey work can be useful in collecting evidence but it is a slow process and any find has to be meticulously recorded. In the aftermath of ancient battles the precious iron would have been collected as it was considered extremely valuable.
Using a geophysical survey can be useful in investigating the area. A radar-altimeter scan of the area can help to pinpoint various areas which would be likely sites.
Community investigation can also be useful. Ask around the area. Has there been something found in the past that is being held in private hands? Is there a family memory or a history' connected to the site? It may be that a local person will be able to say where the land has been disturbed in the past to assist in geo-physical data.
The investigation of modern firearm battles can be much more revealing, especially where it had been impossible to clear the debris of battle. A more thorough picture of the battle can be made from the study of fallen bodies, the pattern of artillery shells and the domestic debris.
Building a picture from the debris of battle and assessing the nature and magnitude of those who had suffered can be a poignant experience for the researcher. Never does the archaeologist forget that their point of interest is focused on the past life of a fellow human being and through the medium of modern science it is sometimes possible to enable that person to transcend space and time to come forth and tell their own individual story.