Faraday depth (ϕ_max) maps of the relic in MACS J0717.5+3745 measured over 1.0–6.5 GHz using RM-synthesis technique. Left: high-resolution (4″) Faraday map. The ϕ_max distribution across the relic, in particular in the northern part is patchy with coherence lengths of 10–50 kpc. Right: low-resolution (12.5″) Faraday depth map. The measured ϕ_max values in the polarized halo region are similar to the R3 region of the relic, indicating very little Faraday rotation intervening material. This suggests that these regions are located on the near side of the cluster.