Mapping the complex and dense arrangement of cells and their connectivity in brain tissue requires volumetric imaging at nanoscale spatial resolution. Light microscopy excels at visualizing specific molecules and individual cells, but dense, synapse-level circuit reconstruction has not yet been achieved.We have developed a light microscopy-based approach to visualize and analyze connectomes in mammalian brain. We base our technology, light-microscopy based connectomics (LICONN) on expansion microscopy to visualize the ultrastructure of nervous tissue, and show traceability of even the finest of neuronal processes. To achieve dense circuit reconstruction with single synapse resolution, we use both conventional and deep-learning based image analysis. In this poster, I will focus on the image and data analysis tools for 3D synapse-level brain tissue reconstruction.