Multiscale Systematic Conservation Planning Across Nested H3 Grids R package MultiscaleSCP version 0.1.1 Provides tools for multiscale systematic conservation planning using the H3 hierarchical hexagonal grid system (Uber Technologies (2024) <https://h3geo.org>) and the 'prioritizr' package (Hanson et al. (2025) <doi:10.1111/cobi.14376>). Supports the definition and solution of conservation problems across nested H3 resolutions with resolution-specific features, costs, and management attributes, including cross-scale connectivity penalties derived from parent-child relationships. Also includes utilities to evaluate solutions using multiscale-aware diagnostics and to post-process optimization outputs into alternative area-targeted conservation scenarios. Software Depends: R (>= 4.2) Imports: sf, terra, raster, dplyr, tibble, Matrix, methods, prioritizr, exactextractr, stats, cli, R6, assertthat, h3jsr, rlang Suggests: ggplot2, rnaturalearth, rnaturalearthdata, rmapshaper, knitr, rmarkdown, testthat (>= 3.0.0) Pablo Merlo <pablo.merlo@universityofgalway.ie> Comprehensive R Archive Network (CRAN) Pablo Merlo [aut, cre] (ORCID: <https://orcid.org/0000-0002-0626-4993>), Oisín Callery [aut] (ORCID: <https://orcid.org/0000-0002-3388-0951>), Carlos Tighe [ctb], Anthony Grehan [ctb] MIT + file LICENSE (https://CRAN.R-project.org/package=MultiscaleSCP/LICENSE) 2026-03-30 application/tgz https://CRAN.R-project.org/package=MultiscaleSCP doi:10.32614/CRAN.package.MultiscaleSCP