%0 Journal Article %T Constructing highly arc transitive digraphs using a layerwise direct product %A Christoph Neumann %J Mathematics %D 2011 %I arXiv %X We introduce a construction of highly arc transitive digraphs using a layerwise direct product. This product generalizes some known classes of highly arc transitive digraphs but also allows to construct new such. We use the product to obtain counterexamples to a conjecture by Cameron, Praeger and Wormald on the structure of certain highly arc transitive digraphs. %U http://arxiv.org/abs/1111.1075v2