The Norwegian Maritime Museum (NMM) holds a substantial collection of complete and incomplete wooden boats, which were found and excavated from the areas known as Barcode and Bjørvika in Oslo. These boats date from the late Middle Ages onwards. Studies of their physical remains have contributed to expanding knowledge of Norwegian maritime history. Waterlogged oak boards and fragments from these boats are stored in large steel containers filled with water while awaiting conservation treatment. As of today, conservators at the NMM have treated the wood with polyethylene glycol before freeze-drying when the wood is fully impregnated. For wood that has been impregnated, freeze-drying is both time-consuming and costly. This Master’s project therefore has aimed to evaluate alternatives. This dissertation presents an analytical study of alternative drying methods to freeze-drying for drying waterlogged archaeological oak from one of the NMM excavations after polyethylene glycol impregnation. Investigations concentrated on the effects of four drying methods: controlled air-drying; uncontrolled air-drying; vacuum-drying; and vacuum freeze-drying, with respect to structural changes. Scanning electron microscopy was a tool for evaluating morphological changes related to the four drying methods. The results from this research suggest further testing of air-drying as an appropriate alternative to freeze-drying. This information aims to help the conservators at NMM to identify drying methods that, in future, might save time and unnecessary expense, while also avoiding damage after drying to their polyethylene glycol impregnated boats.