The Al Haouz earthquake (Mw 6.8) struck Morocco on September 8, 2023, severely affecting the High Atlas Mountains and nearby Marrakesh. These regions are rich in traditional earthen constructions, which experienced significant damage in the shaking. In April 2024, the Earthquake Engineering Field Investigation Team (EEFIT, IStructE UK) deployed a reconnaissance mission to document the impact of the disaster and subsequent recovery efforts. Special attention was paid to traditional constructions and heritage sites. This paper presents findings from field investigations on earthen monuments with a focus on recent conservation interventions using traditional materials and techniques, offering a unique opportunity to evaluate the seismic performance of these retrofits in real conditions. The study highlights two common interventions, crack stitching and wall base widening (base plinths), as documented in monuments such the city walls of Taroudant (12th-16th c.) or Kasbah Taourirt (18th c). Crack stitching using timber keys was effective in reducing wall collapse, particularly under in-plane forces, while rebuilt cracks showed greater stiffness but potentially less energy dissipation. Base plinths improved wall stability by lowering the centre of gravity and reinforcing a vulnerable part of the structure, helping to prevent out-of-plane failure. These observations affirm that traditional materials, when applied according to sound conservation principles and maintained regularly, can significantly enhance the seismic resilience of earthen heritage buildings. The scientific value of post-earthquake fieldwork in heritage contexts is highlighted, calling for further research to assess the mechanical performance of traditional retrofits to develop context-sensitive seismic upgrade guidelines for historic earthen structures.