District heating will have an increasing role in the decarbonization of energy systems and in improving the security of supply. Although the electrification of district heating via heat pumps and heat storage is seen as the main path to decarbonization, green hydrogen could also be an important energy source for covering peak demand, providing long-term storage in power-to-gas solutions and backup. The study's research question was to identify the potential pathways for replacing natural gas in district heating with hydrogen. Should we focus on using hydrogen and build appropriate infrastructure, or should we use hydrogen-derived synthetic gas, for which we already have an infrastructure? A review of publications was the method used in the study. The results show the existing technological solutions and associated costs for using either hydrogen or hydrogen-derived synthetic gas, i.e., methane.