Accessibility has garnered substantial attention from transport and urban planners as the objective of modern transportation systems. However, analyzing accessibility is often challenging in practice due to extensive data requirements and computational complexity. The rapid growth of open data and technology provides new opportunities to perform such analysis in greater details. This study offers a framework for harnessing open data to support accessibility analysis. We applied the proposed framework to the greater area of North Penajam Paser, which is the candidate site to be Indonesia’s future capital. The results suggest that accessibility mapping using open data could be an important toolbox in regional analysis, especially during the early planning phase. It encourages discussions around the problems and alternative solutions for improving citizen access to various opportunities.