Neutron diffraction experiments were carried out on isotopically labelled copper chloride (CuCl₂) salt in a 4 molal aqueous solution. The first- and second-order isotopic difference methods were used to obtain structural information on the hydration structure of the Cu²⁺ and Cl^- ions and to calculate the pair distribution functions g_CuCl(r) and g_ClCl(r) The results confirm the highly distorted nearest-neighbour coordination of Cu²⁺, and give direct evidence that Cu-Cl contacts exist over a range 2.3<or=r (AA)<or=3.5. Analysis of g_ClCl(r) gives consistent information with that of g_CuCl(r) and shows that direct contacts also exist between Cl^- ions, over the range 2.8<or=r (AA)<or=4.2.