opengeos/lidar is a scientific Python library and GIS toolset for delineating nested surface depressions and mounts in digital elevation models (DEMs), with a heavy focus on LiDAR-derived high-resolution terrain data. The core engine implements a level-set method for extracting depression hierarchy, computing geometric attributes such as area, volume, depth, perimeter, and shape metrics, and exporting results as GeoTIFFs, shapefiles, and CSV tables. The package exposes a Python API (MedianFilter, ExtractSinks, DelineateDepressions, DelineateMounts), a PySimpleGUI-based GUI, a placeholder CLI, and an ArcGIS ArcMap/Pro toolbox with scripts for sink extraction, catchment delineation, flow path analysis, and inundation simulation. It also includes data acquisition utilities for USGS NED, 3DEP, and HUC8-based batch processing, plus LiDAR LAS/LAZ reading and DSM generation helpers.