R package rbgm. Facilities for working with Atlantis box-geometry model (BGM) files. Atlantis is a deterministic, biogeochemical, whole-of-ecosystem model. Functions are provided to read from BGM files directly, preserving their internal topology, as well as helper functions to generate ’Spatial’ objects. This functionality aims to simplify the creation and modification of box and geometry as well as the ability to integrate with other data sources.