Trumau Castle is a moated fortress in the Wienerwald region of Lower Austria, first granted to the area's monastery in 1138 by Margrave Leopold IV. The square-shaped structure features three round towers with conical roofs surrounded by water channels forming its defensive moat system. Initially established as a Cistercian grange for agricultural and viticultural management, the manor was transformed into a formal castle in the 17th century. The historic courtyard remains freely accessible to visitors, offering a glimpse of medieval engineering and monastic heritage preserved through centuries.