Alzheimers disease related amyloid peptide, A beta, forms a fibrillar structure through aggregation. The aggregate is stabilized by a salt bridge that is responsible for the formation of an amphiphilic pore that can accommodate water molecules. None of the reported structures of A beta, however, contain water. We present results from molecular dynamics simulations on dimeric A beta fibrils solvated in water. Water penetrates and fills the amphiphilic pore increasing its volume. We observe a thick wire of water that is translationally and rotationally stiff in comparison to bulk water and may be essential for the stabilization of the amyloid A beta protein. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.