US Karst map March 29, 2020 by CascadeGrotto Here’s the new USGS karst map of the 48 contiguous US states in high resolution: https://pubs.usgs.gov/of/2014/1156/pdf/of2014-1156_hi-res-pdfs/of2014-1156_figure_1.pdfHere’s the new USGS karst map of Alaska, Hawaii, and Puerto Rico in high resolution: https://pubs.usgs.gov/of/2014/1156/pdf/of2014-1156_hi-res-pdfs/of2014-1156_figure_2.pdfHere’s a link to the new US karst report, map, kml, gis, etc files: https://pubs.usgs.gov/of/2014/1156/