ATLASGAL is the APEX Telescope Large Area Survey of the Galaxy, an observing programme with the LABOCA bolometer array at APEX, located at 5100 m altitude on Chajnantor, Chile. This survey mapped over 400 square degrees at 870 microns in the inner Galaxy, with a uniform sensitivity of a few solar masses at 1 kpc distance. This project is a collaboration between the Max Planck Gesellschaft (MPG: Max Planck Institute fur Radioastronomie, MPIfR Bonn, and Max Planck Institute fur Astronomie, MPIA Heidelberg), the European Southern Observatory (ESO) and the Universidad de Chile. The APEX telescope is ideally located to observe the inner Milky Way. The Large APEX Bolometer Camera (LABOCA) is a 295-element bolometer array observing at 870 um, with a beam size of 19.2 arcsec. Taking advantage of its large field of view (11.4 arcmin) and excellent sensitivity, we started an unbiased survey of the entire Galactic Plane accessible to APEX, with a typical noise level of 50-70 mJy/beam: the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL). Original acknowledgement for data: This research has made use of the services of the ESO Science Archive Facility