Perturbed angular correlation, Rutherford backscattering and channelling experiments were conducted to study the lattice location and annealing behaviour of 110 keV hafnium ions implanted into iron single crystals. It was found that a fraction of 11-25% of the implanted hafnium atoms are located at substitutional sites in an undisturbed environment, while about 50% are located at irregular lattice sites. The remaining fraction are located at or near regular lattice sites in a perturbed local environment. Trapping and detrapping of monovacancies by substitutional hafnium atoms at 200 and 250 K, respectively, as well as hafnium precipitation during annealing at 873 K was observed. The vacancy-hafnium binding energy was determined to be 0.17(3) eV.