SyHD-atlas presents results of the research project “Syntax hessischer Dialekte” (SyHD, 2010–2016), funded by the Deutsche Forschungsgemeinschaft (DFG), in an electronic format inspired by traditional linguistic atlases. Within SyHD data on 111 tasks, distributed over four questionnaires, were indirectly collected in 161 locations of analysis in the state of Hesse and in 12 non-Hessian comparative locations. The total amount of answered questionnaires is more than 3,500, 799 informants answered all four questionnaires. In the direct elicitation, which was restricted to locations in Hesse, data were collected by five fieldworkers in 140 locations from informants who had answered all four questionnaires. SyHD-atlas presents 185 linguistic maps pertaining to 29 different linguistic phenomena. The maps are accompanied by a description of the phenomenon or construction based on the existing literature.