I am stuck on Elevation: Combine All The Contours Together I downloaded contours for Mississippi (24 tiles) Tried to merge using FWTools, hit the 4gb limit. (Note: Currently FWTools will crash if the file gets over 4gb; if this occurs you must split your contours into two separate folders and combine each half of the state separately. For reference: for Arizona the file was only 3gb.) Did in two chunks, succeeded. Tutorial unclean on how to combine each half of the state separately. Tried to do with both QGIS & ArcMap 10.5 by combining shapefiles. Neither worked. Then both programs started giving errors on drawing each half. Size limit on shapefiles is 2gb?