Gleinstätten is situated west of the Sausal hill range, about halfway between the district cities of Leibnitz and Deutschlandsberg, and approximately 35 km to the south of Styria’s capital, Graz. Its oldest part, with the prominent Renaissance castle, is centered on the eastern and southern edge of a terrace that provides protection against the floods of the river. The villages Prarath, Haslach and Forst (the latter two on the opposite side of the river) are part of the Gleinstätten community.

There are very few neolithic finds, and no Bronze Age finds, at Gleinstätten. However, at this time the hill ranges hemming in the Sulm river were used as an east-to-west transit route between the Balkans, the southern parts of the Basin of Graz and what would much later become the Austrian’s southernmost province, Carinthia.

In the early alpine Iron Age, from the early 8th century BC to the early 600s BC, a significant Hallstatt culture settlement of more than regional importance existed on the Burgstallkogel, a prominent hill just across the Sulm valley. The inhabitants of this settlement maintained long-range trade relations, and it would have been reasonable for them to keep at least a watch post on the terrace on the opposite side of the valley; however, nothing to this effect has been found so far. Only in the 5th century B.C., when the Burgstallkogel settlement was already abandoned, a small and rather poor habitation was present north of Gleinstätten. There is also no proof of a settlement at Gleinstätten during Roman rule when the area was part of the province of Noricum, although the remains of a Villa rustica have been identified near the former Burgstallkogel settlement.

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