Description This package contains aggregated occurrence data ("occurrence cubes") for non-native taxa in Belgium and Europe. These occurrence cubes were generated by grouping species occurrence data from the Global Biodiversity Information Facility (GBIF) by year (year), 1x1km spatial EEA reference grid cell (eea_cell_code) and taxon (taxonKey or classKey). For each grouping, the number of occurrences found in GBIF (n) and the minimum coordinateUncertaintyInMeters (min_coord_uncertainty) are provided. The provided coordinateUncertaintyInMeters of an occurrence is taken into account when assigning it to a grid cell (see this code). The occurrence cubes are used as input data for indicators and risk modelling/mapping for the Tracking Invasive Alien Species (TrIAS) project. The occurrence cubes are built on open science principles and intended to be completely reproducible: The input data are publicly available on GBIF, with the download DOIs listed in the related identifiers of this package. The code to process the data to cubes is publicly available on GitHub at https://github.com/trias-project/occ-cube-alien (version 20191030). Files be_alientaxa_cube.tsv: occurrence cube of alien taxa listed by the Global Register of Introduced and Invasive Species - Belgium (Desmet et al. 2019) and limited to occurrences in Belgium (country=BE). be_alientaxa_info.tsv: taxonomic information for taxa in be_alientaxa_cube.tsv. be_classes_cube.tsv: occurrence cube of all classes found in Belgium (country=BE), used to assess sampling effort bias in be_alientaxa_cube.tsv. eu_modellingtaxa_cube.tsv: occurrence cube of selected modelling species in Europe (bounding box). eu_modellingtaxa_info.tsv: taxonomic information for taxa in eu_modellingtaxa_cube.tsv. ; This work has been funded under the Belgian Science Policies Brain program (BelSPO BR/165/A1/TrIAS).