  The pyrochlore material $\rm Ho_{2}Ti_{2}O_{7}$ has been suggested to show
``spin ice'' behaviour. We present neutron scattering and specific heat results
that establish unambiguously that Ho$_2$Ti$_2$O$_7$ exhibits spin ice
correlations at low temperature. Diffuse magnetic neutron scattering from
Ho$_2$Ti$_2$O$_7$ is found to be quite well described by a near neighbour spin
ice model and very accurately described by a dipolar spin ice model. The heat
capacity is well accounted for by the sum of a dipolar spin ice contribution
and an expected nuclear spin contribution, known to exist in other Ho$^{3+}$
salts. These results settle the question of the nature of the low temperature
spin correlations in $\rm Ho_{2}Ti_{2}O_{7}$ for which contradictory claims
have been made.
