The Overhead Catenary Line System (OCLS) is crucial for continuous electrical supply to trains in electrified railway networks. This article outlines the research conducted on the exploration of the sustainable design space of the Overhead Contact Line support structure on the main Dutch rail network. The research began with a comprehensive review of the literature on OCLS support structures, covering publications from 2013 to 2022. A multi-objective optimisation model is developed to explore sustainable design possibilities. Further result analyses elucidate the defining parameters and variables of the support structure design. The findings presented in this research serve as a basis for more in-depth research on the discussion surrounding existing regulations and specifications and sustainability within the rail branch.