I've been using a fairly old version of mkgmap and getting excellent results. However, I just tried to compile a map using several of the latest releases and keep getting errors. This is the run using r4306 of mkgmap. The command line is the same one I used last week to compile some OSM data from Alaska java -Xmx4000m -jar mkgmap.jar --max-jobs --latin1 --family-id=261 --name-tag-list=name,int_name,alt_name,loc_name,short_name --gmapsupp --description="AlaskaCustom" --country-name=USA --country-abbr=USA --index --location-autofill="is_in,nearest" --copyright-message="ODbL by OSM contributors" --add-pois-to-areas --link-pois-to-ways --reduce-point-density=4 --reduce-point-density-polygon=8 --merge-lines --route --drive-on=detect,right --housenumbers --x-split-name-index --check-roundabouts --check-roundabout-flares --process-destination --process-exits --poi-address --style-file="C:\Users\alask\Dropbox\Mapping\DJS_styles" --generate-sea=land-tag=natural=background --precomp-sea="C:\Users\alask\Downloads\Maps\sea.zip" "C:\Users\alask\Downloads\Maps\Kenai.osm" "C:\Users\alask\Dropbox\Mapping\24983djs.TYP" Time started: Thu May 28 19:50:01 ICT 2020 java.lang.NoClassDefFoundError: crosby/binary/file/BlockReaderAdapter at uk.me.parabola.mkgmap.reader.osm.OsmMapDataSource.<clinit>(OsmMapDataSource.java:79) at uk.me.parabola.mkgmap.reader.MapReader.<clinit>(MapReader.java:42) at uk.me.parabola.mkgmap.main.MapMaker.loadFromFile(MapMaker.java:155) at uk.me.parabola.mkgmap.main.MapMaker.makeMap(MapMaker.java:58) at uk.me.parabola.mkgmap.main.Main$1.call(Main.java:291) at uk.me.parabola.mkgmap.main.Main$1.call(Main.java:287) at java.util.concurrent.FutureTask.run(Unknown Source) at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source) at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) at java.lang.Thread.run(Unknown Source) Caused by: java.lang.ClassNotFoundException: crosby.binary.file.BlockReaderAdapter at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) ... 10 more Exiting - if you want to carry on regardless, use the --keep-going option Any ideas? Thank you, Dave -- Dave Swarthout Homer, Alaska Chiang Mai, Thailand Travel Blog at http://dswarthout.blogspot.com