Attack graphs quickly become large and challenging to understand and overview. As a means to ease this burden this paper presents an approach to introduce conceptual hierarchies of attack graphs. In this approach several attack steps are aggregated into abstract attack steps that can be given more comprehensive names. With such abstract attack graphs, it is possible to drill down, in several steps, to gain more granularity, and to move back up. The approach has been applied to the attack graphs generated by the cyber threat modeling tool securiCAD.